Berry Big Crowd-Pleaser: Raspberry Buttermilk Slab Pie Recipe

A sweet-tart summer slab pie with creamy buttermilk custard, juicy raspberries, and a buttery homemade crust made for cookouts, potlucks, and “just one more tiny slice” moments.

This Raspberry Buttermilk Slab Pie Recipe is what happens when summer berries meet old-fashioned buttermilk pie and decide to bring enough dessert for the whole picnic table. It is creamy, bright, buttery, a little tangy, and berry much the dessert that shows up looking humble but leaves with applause.

If you have ever wished a classic buttermilk pie could feed more than a few polite slices, slab pie is your answer. Baked in a 13 x 9½-inch jelly roll pan, this raspberry slab pie recipe gives you that dreamy custard filling, a golden homemade crust, and fresh raspberries in every bite without requiring you to make three separate pies for a crowd.

It is perfect for summer gatherings, potlucks, backyard BBQs, family reunions, church suppers, and berry season celebrations. It also belongs right at home on your holiday dessert table, especially if you are planning a sunny spread from my Memorial Day Recipes & Party Ideas hub. Think grilled favorites, cold sides, patriotic treats, and one creamy raspberry buttermilk pie that quietly steals the whole show.

 

Why You’ll Love This Raspberry Buttermilk Slab Pie Recipe

This pie is the dessert version of showing up with a covered dish and leaving with an empty pan. It has that nostalgic buttermilk pie flavor—smooth, custardy, lightly tangy, and sweet—but the raspberries add a fresh pop that keeps every bite bright and summery.

• It feeds a crowd. A slab pie is ideal for potlucks, cookouts, holiday parties, and family gatherings because it cuts into easy squares.
• Fresh raspberries shine. The berries bake into the custard, adding sweet-tart flavor and gorgeous color.
• The homemade crust is buttery and sturdy. It holds up beautifully under the creamy filling.
• It feels special without being fussy. The finished pie looks bakery-worthy, but the steps are approachable.
• It is a summer dessert workhorse. Serve it chilled, room temperature, plain, dusted with powdered sugar, or topped with whipped cream.

And if berries are your happy place, you may also want to serve this alongside my Easy Strawberry Pie Recipe or this colorful Fresh Fruit Tart for a berry-forward dessert table that practically sparkles.

What Is a Raspberry Buttermilk Slab Pie?

A raspberry buttermilk slab pie is a rectangular pie baked in a shallow sheet pan or jelly roll pan instead of a round pie plate. It has a buttery homemade crust, a creamy buttermilk custard filling, and fresh raspberries scattered throughout.

Traditional buttermilk pie is known for its simple custard filling made with buttermilk, eggs, sugar, butter, and vanilla. This version gets a summer glow-up with fresh raspberries and a slab pie format that makes it easier to slice and serve to a crowd.

The flavor is rich but not heavy. The buttermilk adds tang, the raspberries add brightness, and the crust gives every square that golden, flaky edge everyone secretly hopes lands on their plate.

Ingredients for Raspberry Buttermilk Slab Pie

This recipe uses classic baking staples plus fresh raspberries. For the best flavor and texture, keep the butter cold for the crust and use ripe, firm raspberries for the filling.

For the Pie Crust

• 2 ½ cups all-purpose flour: The base of the crust. Spoon and level for best results.
• 2 tablespoons Sugar in the Raw: Adds a subtle sweetness and a little texture to the crust.
• 1 teaspoon sea salt: Balances the sweetness and enhances the buttery flavor.
• 1 cup cold butter, cut into cubes: Cold butter creates flaky layers. Keep it chilled until ready to use.
• ½ cup ice water: Helps bring the dough together without warming the butter.
• 1 egg white whisked with 2 teaspoons cool water: Used as an egg wash to help seal the crust and give the edges a pretty finish.

For the Raspberry Buttermilk Filling

• 1 ¾ cups buttermilk: Gives the custard its classic tangy flavor.
• 3 eggs: Help the filling set into a creamy custard.
• ¼ cup butter, melted: Adds richness and a silky texture.
• 1 tablespoon lemon juice: Brightens the berries and balances the sweetness.
• 1 ½ teaspoons pure vanilla extract: Rounds out the custard flavor.
• 1 cup Sugar in the Raw plus 2 tablespoons, divided: Sweetens the filling and adds sparkle to the crust edges.
• 2 teaspoons cornstarch: Helps stabilize the custard filling.
• ½ teaspoon sea salt: Keeps the filling from tasting flat.
• 3 cups fresh raspberries: The berry beautiful star of the show.

No Buttermilk? No Pie Panic.

Buttermilk is what gives this raspberry buttermilk slab pie its creamy custard texture and gentle tang, so it is worth using the real thing when you can. But if your fridge is giving you attitude and the buttermilk is nowhere to be found, do not abandon dessert. You can use this easy buttermilk substitute to keep the pie party moving.

For best results, mix your substitute first and let it rest before adding it to the custard filling. That little pause helps the flavor and texture behave more like traditional buttermilk.

How to Make Raspberry Buttermilk Slab Pie

This pie has three main parts: making the crust, blind baking the crust, and adding the raspberry buttermilk filling. The extra chilling and blind baking steps are worth it because they help prevent a soggy bottom and give the custard a sturdy, golden crust to settle into.

Step 1: Make the Homemade Pie Crust

In the bowl of a food processor, add the flour, Sugar in the Raw, and sea salt. Pulse a few times to combine. If you are making the crust by hand, add the flour, sugar, and salt to a large mixing bowl and whisk together.

Add the cold cubed butter. Pulse until the mixture looks crumbly and the butter is in pea-sized pieces. If working by hand, use a pastry blender or two knives to cut the butter into the flour mixture.

Add half of the ice water and pulse or stir to combine. Continue adding the remaining ice water a little at a time, just until the dough comes together into a shaggy ball. Be careful not to overwork it. Pie dough likes a gentle hand, not a full workout routine.

Turn the dough out onto a lightly floured work surface. Knead lightly just until it forms a smooth ball, then flatten it into a rectangle. Wrap the dough in plastic wrap and chill for at least 1 hour or overnight.

Step 2: Prepare the Pan and Roll the Dough

Lightly grease a 13 x 9½ x 1-inch baking sheet or jelly roll pan. Preheat the oven to 375°F.

Lightly flour your work surface and place the chilled dough on top. Roll the dough into a rectangle about 2 inches larger than the baking sheet on all sides. Use even pressure with your rolling pin so the dough stays as uniform as possible.

If the dough cracks, let it rest for a few minutes to warm slightly, then continue rolling. Patch any holes or larger cracks with excess dough. Loosely roll the dough around the rolling pin and transfer it to the prepared baking sheet.

Trim the edges of the dough to leave about a ¾-inch overhang, then crimp the edges. Poke the dough all over with a fork, then chill it for 30 minutes.

Step 3: Blind Bake the Crust

Line the chilled crust with parchment paper and fill it to the brim with pie weights or dried beans. Blind bake the crust until the edges are brown and set, about 20 minutes.

Carefully remove the pie weights and parchment paper. Brush the crust with the egg white mixture, then return it to the oven for 5 minutes more to help set the bottom of the crust.

Step 4: Make the Buttermilk Custard Filling

In a large mixing bowl, whisk together the buttermilk, eggs, melted butter, lemon juice, and vanilla extract until smooth.

In a separate medium mixing bowl, whisk together 1 cup Sugar in the Raw, cornstarch, and sea salt. Whisk the sugar mixture into the buttermilk mixture until fully combined.

Step 5: Add the Raspberries and Bake

Sprinkle the fresh raspberries evenly over the blind-baked pie crust. Pour the buttermilk custard filling over the raspberries.

Brush the crust edges with more egg wash and sprinkle with the remaining 2 tablespoons of Sugar in the Raw.

Reduce the oven temperature to 350°F. Bake for 35 to 40 minutes, or until the edges are set and the center of the custard jiggles slightly, similar to gelatin.

Transfer the pie to a cooling rack and let it cool completely before cutting. Refrigerate leftovers.

Expert Tips for the Best Raspberry Slab Pie

A good slab pie should slice cleanly, hold its shape, and make people hover near the dessert table. These tips help get you there.

• Keep the butter cold. Cold butter is the secret to a flaky crust. If the dough gets too soft while rolling, pause and chill it again.
• Do not skip the blind bake. The custard filling is wet, so blind baking helps protect the crust from becoming soggy.
• Use fresh raspberries when possible. Fresh berries hold their shape better and release less liquid than frozen berries.
• Let the pie cool completely. The custard continues to set as it cools. Cutting too soon can lead to messy slices.
• Watch the jiggle. The center should wobble slightly, but it should not look liquid.
• Chill for cleaner squares. If you want picture-perfect slices, refrigerate the cooled pie before cutting.

Can I Use Frozen Raspberries?

Fresh raspberries work best for this raspberry buttermilk slab pie recipe, but frozen raspberries can be used in a pinch. Do not thaw them completely before adding them to the crust, or they may release too much juice and tint the custard.

If using frozen raspberries, toss them lightly with a teaspoon or two of cornstarch before adding them to the crust. This can help manage extra moisture and keep the filling from becoming too loose.

Variations and Creative Ideas

Once you have the basic raspberry buttermilk slab pie down, you can play with the flavors like summer handed you a mixing spoon and said, “Go on, have fun.”

Mixed Berry Buttermilk Slab Pie

Swap part of the raspberries for blueberries, blackberries, or sliced strawberries. This is especially pretty for patriotic cookouts and pairs beautifully with other berry desserts like Strawberry Basil Hand Pies.

Lemon Raspberry Buttermilk Pie

Add 1 teaspoon of lemon zest to the custard filling for extra brightness. Lemon and raspberry are best friends, and this version tastes like sunshine borrowed a pie plate.

Almond Raspberry Slab Pie

Add ¼ teaspoon almond extract along with the vanilla. A little almond extract goes a long way, so keep it light.

Powdered Sugar Finish

Once the pie is fully cooled, dust the top with powdered sugar right before serving. It adds a bakery-style finish without much effort.

Whipped Cream Topping

Serve each square with a dollop of whipped cream. For a lighter dessert table, you could pair this pie with Angel Food Cake with Marshmallow Topping, especially for spring and summer gatherings.

Serving Suggestions for Summer Cookouts and Potlucks

This raspberry buttermilk slab pie is made for sharing, which makes it a natural fit for warm-weather menus. Cut it into squares and serve it chilled or at room temperature.

For a Memorial Day cookout, pair this creamy raspberry pie with classic grilled mains, chilled salads, and easy sides from the Memorial Day Recipes & Party Ideas collection. It brings a fresh berry finish to smoky BBQ flavors and sunny picnic plates.

For a dessert spread, serve it with Easy Strawberry Pie, Fresh Fruit Tart, or a cool scoop of Homemade Piña Colada Ice Cream. The combination gives guests a little creamy, a little fruity, and a lot of “I need the recipe.”

More Berry Desserts and Summer Sweets to Try

If this raspberry buttermilk slab pie has you in a berry-baking mood, keep the summer dessert momentum going with a few reader-friendly favorites. For another fresh pie option, try my Easy Strawberry Pie. If you want a creamy make-ahead bar dessert, these Blueberry Cheesecake Bars are perfect for potlucks and party trays.

For a showstopping fruit dessert, the Fresh Fruit Tart brings bright berries and a pretty bakery-style finish. If handheld desserts are more your picnic-table personality, add Strawberry Basil Hand Pies to the menu. And for something light, fluffy, and nostalgic, serve this pie alongside Strawberry Angel Food Cake with Marshmallow Topping or Strawberry Shortcake Cupcakes.

Make It Part of a Memorial Day Dessert Table

This raspberry slab pie recipe is a natural fit for cookouts, potlucks, and patriotic summer parties because it slices into easy squares and brings that red-and-creamy dessert-table moment without needing a fussy flag cake. For a full holiday spread, pair it with more ideas from my Memorial Day Recipes & Party Ideas hub, where you’ll find cookout mains, sides, drinks, snacks, and easy summer desserts made for sharing.

If you are building a red, white, and blue dessert lineup, this pie plays beautifully with Easy Strawberry Pie, Blueberry Cheesecake Bars, and Red White & Cool Cubes for a party table that feels festive, fresh, and Pinterest-ready.

How to Store Raspberry Buttermilk Slab Pie

Because this pie has a custard filling, leftovers should be refrigerated. Cover the pan tightly with plastic wrap or transfer slices to an airtight container. Store in the refrigerator for up to 3 days.

For the cleanest texture, let chilled slices sit at room temperature for 10 to 15 minutes before serving. This softens the custard slightly and brings back that creamy, dreamy bite.

Can You Make Raspberry Buttermilk Slab Pie Ahead of Time?

Yes, and that is one of the reasons this pie is so handy for entertaining. You can make the crust dough the day before and keep it wrapped in the refrigerator overnight. You can also bake the entire pie a day ahead, cool it completely, cover it, and refrigerate until ready to serve.

For best presentation, slice the pie shortly before serving. If you are transporting it to a potluck, keep it chilled and cut it once you arrive.

FAQs About Raspberry Buttermilk Slab Pie

What does buttermilk pie taste like?

Buttermilk pie has a creamy custard filling with a gentle tang, buttery richness, and vanilla sweetness. In this raspberry version, the fresh berries add sweet-tart flavor that balances the custard beautifully.

Do I have to blind bake the crust?

Yes, blind baking is recommended for this raspberry slab pie recipe because the buttermilk custard is a wet filling. Blind baking helps the crust set before the filling is added, which helps prevent a soggy bottom.

Can I make this raspberry buttermilk pie in a regular pie dish?

This recipe is designed for a 13 x 9½ x 1-inch baking sheet or jelly roll pan. A regular pie dish will not hold the same amount of crust and filling. For best results, use the pan size listed.

How do I know when buttermilk slab pie is done?

The edges should be set, and the center should jiggle slightly like gelatin. It should not slosh or look liquid. The pie will continue to set as it cools.

Can I use a store-bought crust?

A homemade crust gives this pie the best flavor and structure, but store-bought pie dough can work if you use enough to fit the slab pan with overhang. You may need more than one refrigerated crust to cover the pan properly.

Can I freeze raspberry buttermilk slab pie?

Freezing is not ideal because custard fillings can change texture after thawing. This pie is best enjoyed fresh or refrigerated for a few days.

Is this pie best served warm or cold?

This raspberry buttermilk slab pie is best served fully cooled, chilled, or slightly cool. Cooling allows the custard to set and makes slicing much easier.

More Summer Dessert Ideas

If your dessert table has room for one more sweet thing—and let’s be honest, dessert tables always do—try pairing this pie with more fruit-forward favorites. The Easy Strawberry Pie Recipe brings glossy berry goodness, while the Fresh Fruit Tart adds color and elegance. For grab-and-go charm, Strawberry Basil Hand Pies are perfect for picnics, lunchboxes, and casual summer gatherings.

Planning a full warm-weather menu? Loop this pie into your Memorial Day Recipes & Party Ideas spread so readers can move easily from cookout mains and sides to the sweet finish.

Final Thoughts on Raspberry Buttermilk Slab Pie

This Raspberry Buttermilk Slab Pie Recipe is creamy, bright, and made to feed a crowd without making dessert feel complicated. It has the cozy charm of an old-fashioned buttermilk pie, the fresh pop of summer raspberries, and the practical magic of a slab pie that slices neatly for parties, potlucks, and backyard gatherings.

It is the kind of dessert that feels right at home on a picnic table, a holiday buffet, or a quiet Sunday afternoon when the berries looked too good to leave behind at the store. Serve it chilled, slice it into squares, and let everyone decide whether they are having a corner piece, an edge piece, or “just a tiny one” that somehow turns into seconds.

This recipe was originally published May 3, 2018, and updated May 25, 2026, with improved instructions, updates, and new photos.