Blueberry Slab Pie

Introduction

This Blueberry Slab Pie is the ultimate dessert for feeding a crowd, combining the nostalgic flavor of a classic blueberry pie with the ease of baking in a sheet pan. You get a perfect ratio of flaky crust to juicy, spiced filling in every generous slice. It’s a showstopping treat that’s surprisingly straightforward to make.

This recipe and accompanying image were created with the help of AI for inspiration and guidance. Results may vary depending on ingredients, equipment, and technique.

Prep & Cook Time

Prep Time: 20 minutes
Cook Time: 90 minutes
Total Time: 1 hour 50 minutes
Servings: 20

Ingredients

8 cups wild blueberries
2 1/2 cups granulated sugar
1/4 cup lemon juice
3/4 cup instant tapioca
1/2 teaspoon ground cinnamon
3/4 teaspoon ground nutmeg
pie crust (recipe for 2 double crust pies)
granulated sugar (for dusting the top of the pie)
egg wash

Instructions

Preheat your oven to 375°F (190°C). Prepare a rimmed 13×18-inch sheet pan.
In a very large bowl, gently combine the wild blueberries, granulated sugar, lemon juice, instant tapioca, ground cinnamon, and ground nutmeg. Let the mixture sit for 15 minutes to allow the tapioca to begin absorbing the juices.
Roll out half of the pie crust dough into a large rectangle slightly bigger than your sheet pan. Carefully transfer it to the pan, letting the edges drape over the sides.
Pour the blueberry filling into the crust-lined pan, spreading it into an even layer.
Roll out the remaining pie crust dough. You can place it over the filling as a full top crust, or cut it into strips to create a lattice pattern. Seal and crimp the edges.
Brush the top crust generously with the egg wash. Sprinkle liberally with granulated sugar for dusting.
Bake for about 85-90 minutes, or until the crust is deep golden brown and the filling is bubbling vigorously.
Transfer the pan to a wire rack and allow the pie to cool completely, for at least 4 hours, before slicing. This ensures the filling sets properly.

Variations

Individual Hand Pies: Use the same filling and crust to create smaller, portable hand pies.
Crumb Topping: Instead of a top crust, cover the filling with a buttery streusel crumb topping before baking.
Flavor Infusion: Add a teaspoon of vanilla extract or the zest of a lemon to the blueberry filling for an extra layer of flavor.
À La Mode Serving: Serve each warm slice with a scoop of vanilla ice cream for a classic combination.

Tips for Success

Let the filling sit with the tapioca as directed; this step is crucial for preventing a runny pie.
Ensure your oven is fully preheated and use the middle rack for even baking.
Don’t skip the cooling time. Cutting into the pie while it’s warm will result in a soupy filling.
If the crust edges begin to brown too quickly, tent them with strips of aluminum foil.

Storage & Reheating

Once completely cooled, cover the pie tightly with plastic wrap or foil and store at room temperature for up to 2 days, or in the refrigerator for up to 4 days. To reheat, place individual slices on a baking sheet in a 300°F (150°C) oven for 10-15 minutes until warm.

FAQ

Can I use frozen blueberries?

What can I use instead of instant tapioca?

The recipe is formulated for instant tapioca, which provides a clear, firm set. Substituting may change the final texture. If necessary, an equal amount of cornstarch can be used, but the filling may be slightly softer.

Why does my pie need to cool for so long?

The cooling period is when the tapioca fully sets and thickens the fruit juices. Slicing too soon will lead to a filling that spills out.

Can I make this pie ahead of time?

Absolutely. You can assemble the pie, cover it tightly, and refrigerate it overnight before baking. Add a few extra minutes to the bake time if starting from cold.

What’s the best way to move the bottom crust to the pan?

Roll the dough onto your rolling pin, then carefully unroll it over the sheet pan. Alternatively, you can fold the dough into quarters, place the corner in the center of the pan, and gently unfold it.

My crust edges are burning. What should I do?

This is common with long bake times. Shield the edges by covering them with strips of aluminum foil about halfway through the baking process.