For the ideal fruit-to-streusel ratio, ditch the deep casserole dish and opt for a shallow sheet pan. Not only does this cook faster, but it means more crunchy topping in every bite.
- 4 pounds (about 8) Granny Smith apples, peeled, cored, and cut into eighths
- 2/3 cup (141 grams) light brown sugar
- 1/4 cup (32 grams) all-purpose flour
- 1/4 teaspoon kosher salt
- 2 1/2 cups (320 grams) all-purpose flour
- 1 2/3 cups (164 grams) rolled oats
- 1 1/4 cups (266 grams) light brown sugar
- 1 1/2 teaspoons kosher salt
- 2 1/2 sticks (283 grams) unsalted butter, somewhere between cold and room temperature, cubed
HOW TO PREPARE
- Heat the oven to 400°F.
- Add all the ingredients for the apple filling to an 18×13-inch rimmed sheet pan (aka, a half sheet pan). Toss with your hands until the sugar begins to dissolve. Spread out the mixture so it’s as even as possible.
- Make the streusel topping: Combine the flour, oats, sugar, and salt in a large mixing bowl. Stir to combine. Add the butter and pinch with your fingers and squeeze with your palms until it’s completely incorporated, and the mixture almost resembles cookie dough. Break up this streusel on top of the apples, evenly distributing it across the pan.
- Bake for 30 to 40 minutes (in the middle of the oven, rotating halfway through), or until the streusel is lightly golden-brown on top. Keep in mind that it will continue to crisp as it cools and you don’t want to overcook the apples.
- Let cool for at least 15 minutes before using a spatula to serve up big squares. This is great warm or at room-temperature the next day.