There’s just something about a slab pie that feels extra cozy and generous, don’t you think? Maybe it’s the way it fills a whole baking sheet with golden crust, sweet jammy filling, and buttery streusel—or the fact that it slices up into neat little squares that you can sneak straight from the pan. Either way, this Blueberry Slab Pie is one of my favorite ways to bake for a crowd… or to treat myself to a square with coffee every day of the week. (No shame in that game.)
This recipe is as homey and rustic as it gets, with an easy press-in crust, a juicy blueberry filling that comes together in minutes on the stovetop, and a crispy oat-studded crumble on top. It’s low-fuss, high-reward baking, and I’m here for it.
Whether you’re heading to a potluck, baking for a brunch gathering, or just in the mood for something fruity and nostalgic, this slab pie is a total win. Plus, the whole thing comes together with pantry basics—flour, sugar, butter, oats, and a few fresh blueberries (or frozen ones if you’re pulling this together in the off-season).
Let’s get started!
Ingredients You’ll Need
Before we dive into the steps, here’s a quick look at what you’ll need. Nothing fancy—just good, solid ingredients that come together to make something special.
For the Crust & Streusel:
300 g all-purpose flour
100 g granulated sugar
1 teaspoon baking powder
¼ teaspoon salt
200 g cold unsalted butter, cubed
1 large egg, lightly beaten
1 teaspoon pure vanilla extract
50 g rolled oats
For the Filling:
600 g fresh or frozen blueberries
150 g granulated sugar
2 tablespoons cornstarch
1 tablespoon fresh lemon juice
1 teaspoon finely grated lemon zest
Pinch of salt
STEP 1: Make the Dough (Crust + Streusel Combo)
In a large mixing bowl, combine your flour, granulated sugar, baking powder, salt, and oats. These are the base dry ingredients for both your crust and streusel topping, which keeps things simple and cuts down on prep time.
Now, grab your cold, cubed butter and cut it into the dry mix using a pastry cutter or a sturdy fork. You’re aiming for a crumbly mixture that resembles coarse sand, with some pea-sized chunks of butter still visible. Those little bits of butter are key—they’ll melt in the oven and create the most tender, flaky texture.
Once the mixture is nice and crumbly, stir in the beaten egg and vanilla extract. Mix just until the dough starts to come together. You don’t want to overwork it—rustic is the name of the game here.
Now, scoop out about one-third of the mixture and set it aside. That’ll become your streusel topping later. The rest? That’s your crust.
STEP 2: Press the Crust Into the Pan
Lightly grease a rimmed baking sheet (about 30 by 40 cm is perfect). Take the larger portion of your dough and press it evenly into the bottom of the pan. Don’t worry about perfection—just make sure it’s an even layer that reaches the edges.
Once you’ve got your crust in place, pop the pan into the fridge while you make the filling. Chilling the dough helps it firm up, which means a flakier bite once it bakes.
STEP 3: Cook the Blueberry Filling
While your crust chills, it’s time to make that gorgeous blueberry filling. In a medium saucepan, combine the blueberries (thawed and drained if using frozen), granulated sugar, cornstarch, lemon juice, lemon zest, and a pinch of salt.
Set the pan over medium heat and cook the mixture, stirring frequently, for about 5 to 7 minutes. You’ll know it’s ready when the berries start to burst and the juices thicken into a glossy, jammy consistency.
Once the filling has thickened, remove the pan from the heat and let it cool for a few minutes. It doesn’t need to be completely cold, but you don’t want it piping hot when it goes on the crust.
Assembly, Baking, and Pro Tips
Alright, now that your blueberry filling is thickened and your crust is nice and chilled, it’s time to bring it all together! This is where the magic really starts to happen—juicy fruit, buttery crumbs, and that heavenly smell that fills your kitchen while it bakes.
One of the things I love about this slab pie is how simple it is to assemble. No rolling pins, no lattice weaving—just spread, sprinkle, and bake. Let’s pick up right where we left off.
STEP 4: Spread the Filling
Pull your prepared crust from the fridge. It should feel slightly firm to the touch, which means it’s ready to support that delicious blueberry layer.
Spoon the slightly cooled blueberry filling evenly over the crust, spreading it all the way to the edges. You want a nice, even layer so every bite has a good amount of fruit. Don’t worry if it looks a little rustic—this pie is all about that relaxed, homemade charm.
STEP 5: Add the Streusel Topping
Take that reserved one-third portion of dough we set aside earlier. This becomes your streusel topping! Give it a quick toss with your fingers to break up any large clumps, then sprinkle it evenly over the blueberry layer.
Gently press the streusel into the filling—just enough so it sticks a bit, but not so much that it sinks in. The oats in the topping will toast up beautifully, adding a little crunch that balances the soft filling and tender crust.
STEP 6: Bake It Up
Preheat your oven to 180°C (that’s about 350°F if you’re baking stateside). Once the oven is ready, slide your slab pie in and bake for 35 to 40 minutes.
You’re looking for a golden brown top, bubbling edges, and maybe a little filling peeking up between the streusel crumbles. That’s when you know it’s done. The smell alone will tell you you’re on the right track.
When it’s finished baking, transfer the pan to a wire rack and let it cool completely. I know—it’s hard to wait. But this step is key! The filling sets up as it cools, making it easier to slice into those perfect, bakery-style squares.
Tips for Success
Use Cold Butter: Cold butter is what makes the crust and streusel flaky and tender. If your kitchen runs warm, you can pop the cubed butter into the freezer for 5–10 minutes before mixing.
Don’t Skip the Chill: Chilling the crust helps it hold up under the juicy filling, and it keeps the butter from melting too quickly in the oven.
Let It Cool Completely: This is tough, especially when your kitchen smells like a blueberry wonderland. But cooling the slab pie fully ensures clean slices and the best texture.
Glossier Filling Option: If you want that glossy bakery-style shine, stir a tablespoon of maple syrup into the cooked blueberry filling before spreading it onto the crust. It adds just a hint of depth and gloss.
Variations and Serving Ideas
Switch the Fruit: Not feeling blueberries? You can easily swap in raspberries, blackberries, or chopped strawberries. Just keep the total weight close to 600 g and adjust sugar to taste (especially if the fruit is extra tart).
Add a Drizzle: Once cooled, a simple powdered sugar glaze (just icing sugar mixed with a little milk or lemon juice) adds a sweet finishing touch.
Serve Warm or Chilled: Personally, I love it at room temperature with a scoop of vanilla ice cream or a dollop of whipped cream, but it’s just as tasty cold for breakfast with coffee.
Make It Ahead: This pie is fantastic the next day, and even better on day two. The flavors deepen and the crust stays crisp if stored properly.
FAQs and Final Thoughts
We’ve baked, filled, and topped this blueberry slab pie to perfection—but before you preheat that oven and dive in, let’s run through a few of the most common questions that come up with this kind of recipe. Whether you’re new to slab pies or just want to make sure yours turns out bakery-worthy, these answers will help you feel extra confident.
Frequently Asked Questions
Can I use frozen blueberries instead of fresh?
Yes, absolutely! Just be sure to thaw and drain them well first. Excess liquid from frozen berries can water down the filling, so pat them dry a bit before cooking. The filling will still be delicious and just as vibrant.
How do I know when the slab pie is done baking?
Look for golden brown streusel and bubbling edges of filling. If your oven runs hot or cool, you might need to adjust the baking time slightly, but 35–40 minutes is usually just right. A little bubbling around the edges is a good sign that the cornstarch has thickened the filling.
Can I make the crust ahead of time?
Yes! You can prepare the dough (crust and streusel mixture) a day ahead and keep it refrigerated in an airtight container. When you’re ready to bake, just press it into the pan, chill the base briefly, and continue as usual.
What’s the best way to store leftovers?
Leftover pie can be stored in an airtight container at room temperature for up to two days, or in the fridge for up to five days. I like to reheat individual slices in the oven at a low temperature to crisp up the streusel topping again.
Can I freeze blueberry slab pie?
Yes, but with a few notes. Once cooled completely, slice the pie and freeze the squares on a baking sheet before transferring them to a freezer-safe container. Thaw overnight in the fridge, then reheat in a warm oven. The texture of the streusel may soften a bit, but the flavor holds up beautifully.
Why is my crust soggy on the bottom?
If you skip the chilling step or use berries with too much liquid, the crust can get soggy. Make sure your filling isn’t too wet, and always chill your pressed-in crust before baking. It helps create a firmer base once baked.
Can I halve the recipe?
Definitely. If you’re baking for a smaller group, cut all ingredients in half and use a smaller baking pan—something around 9×13 inches works well. The baking time will be close to the same, just start checking around 30 minutes.
Final Thoughts: Why This Slab Pie Belongs in Your Recipe Rotation
There’s something undeniably nostalgic about blueberry desserts, and this slab pie hits all the right notes: jammy fruit, tender crust, a buttery crumble on top—and all baked up in one big tray that’s made for sharing (or hoarding, no judgment here). It’s the kind of bake that works just as well for a weekend treat as it does for feeding a house full of guests.
One of the things I appreciate most about this recipe is how forgiving it is. You don’t need fancy equipment or pie-making experience—just a few bowls, a baking sheet, and a love for blueberries. It’s versatile, too. You can swap the fruit, tweak the topping, or add a glaze depending on your mood.
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Blueberry Slab Pie
Description
This rustic blueberry slab pie features a tender buttery crust topped with a sweet-tart blueberry filling and a golden streusel. Baked on a rimmed baking sheet for easy slicing, it’s perfect for feeding a crowd or enjoying week-long snacking.
Ingredients
300 g all-purpose flour
100 g granulated sugar
1 teaspoon baking powder
¼ teaspoon salt
200 g cold unsalted butter, cut into cubes
1 large egg, lightly beaten
1 teaspoon pure vanilla extract
50 g rolled oats
Ingredients for filling
600 g fresh or frozen blueberries
150 g granulated sugar
2 tablespoons cornstarch
1 tablespoon fresh lemon juice
1 teaspoon finely grated lemon zest
pinch of salt
Instructions
Combine flour, sugar, baking powder, salt and oats in a large bowl and cut in the cold butter with a pastry cutter or fork until the mixture resembles coarse crumbs. Stir in the beaten egg and vanilla until the dough just comes together, reserving about one third of the mixture for the streusel.
Press the remaining dough evenly into a lightly greased rimmed baking sheet (approximately 30 by 40 cm) forming a uniform base. Chill in the refrigerator while preparing the filling.
In a medium saucepan combine blueberries, sugar, cornstarch, lemon juice, lemon zest and salt. Cook over medium heat, stirring frequently until the mixture thickens and the berries begin to burst, about 5 to 7 minutes. Remove from heat and let cool slightly.
Spread the blueberry filling evenly over the chilled crust. Sprinkle the reserved streusel mixture over the top, pressing gently so it adheres.
Bake in a preheated 180 °C oven until the streusel is golden and the filling is bubbling, about 35 to 40 minutes. Allow the slab pie to cool completely on a wire rack before slicing into squares or rectangles.
Notes
Frozen blueberries work well but should be thawed and drained to prevent excess liquid. For a glossier filling stir a tablespoon of maple syrup into the cooked fruit before spreading. Leftover pie can be stored in an airtight container at room temperature for up to two days or refrigerated for up to five days. Reheat individual pieces briefly in a warm oven to revive the crisp streusel.
