cook's illustrated blueberry pie
This might be the pie that taught me how to make pies. It’s arguably Cook’s Illustrated most famous pie recipe (or most famous recipe, period) and for good reason: the filling. This is the recipe where Cook’s Illustrated first used quick-cooking tapioca as a thickening agent. Pre-cooked and pulverized in a coffee grinder, the tapioca easily dissolves during baking, better than ground pearl tapioca, which can leave remnants of tiny gelatinous spheres. The quick-cooking tapioca also thickens without messing with flavor, unlike starches and flours which can leave a cardboard aftertaste. But in this recipe, it’s not just about the choice of thickener. Overall, less tapioca is needed because the filling is naturally thickened in two other ways: 1) by mashing up and cooking down half of the blueberries and 2) by adding a grated apple, which has a lot of natural pectin. The green apple adds a hint of welcome tartness, but is otherwise indiscernible. And the mashed-up blueberries double down on the flavor and texture, yielding a pie that tastes super-blueberry-y, with a mix of jammy berries and whole ones that pop. The consistency is Goldilocks-perfect: not too pasty, not too soupy. A pie fit for a picture book, and then some.
Cook’s Illustrated Blueberry Pie
Adapted from Cook’s Illustrated.
Makes one 9-inch pie.
Although I use my own pie dough, I’m still calling this a Cook’s Illustrated recipe because I’ve made no significant changes to that revelatory blueberry filling. This is truly best with fresh blueberries, but unthawed frozen ones will work (Wyman’s is a good brand). Please see the link below not only for my pie dough recipe, but for instructions on rolling and crimping the dough.
THE BUTTER LAB’S PIE DOUGH (ROLLED OUT AND CHILLED FOR A DOUBLE-CRUST PIE)
6 cups fresh blueberries (about 30 ounces)
1 Granny Smith apple, peeled and grated on large holes of box grater
2 teaspoons zest and 2 teaspoons juice from 1 to 2 lemons
3/4 (5 1/4 ounces) cup sugar
2 tablespoons quick-cooking tapioca
1/8 teaspoon kosher salt
1 large egg, lightly beaten with 1 teaspoon water
Turbinado or Demerara sugar for sprinkling (optional)
Position oven racks in the bottom and center positions, and preheat the oven to 425°F.
In a coffee grinder (or food processor), grind instant tapioca for 30 seconds and set aside.
Place 3 cups berries in medium saucepan and set over medium heat. Using potato masher, mash berries several times to release juices. Continue to cook, stirring frequently and mashing occasionally, until about half the berries have broken down and mixture is thickened and reduced to 1 1/2 cups, about 8 minutes. Let cool slightly.
Place grated apple in clean kitchen towel and wring dry. Transfer apple to large bowl. Add cooked berries, remaining 3 cups uncooked berries, lemon zest, juice, sugar, tapioca, and salt; toss to combine.
Transfer mixture to dough-lined pie plate, cover with top crust, and seal-crimp (see pie dough directions). Brush with egg wash mixture and sprinkle with Turbinado sugar, if using. Place pie pan on a parchment-lined baking sheet. Bake on the bottom oven rack for 20 to 25 minutes, or until the pastry is set and beginning to brown. Lower the oven temperature to 375°F, move the pie to the center oven rack, and continue to bake until the pastry is a deep golden brown and the juices are bubbling throughout, 30 to 35 minutes longer. Allow to cool completely on a wire rack, at least 4 hours.