In a medium bowl, combine the flour, brown sugar, salt, baking powder, and cinnamon. Stir to combine.
1 ¼ cups all purpose flour, ¾ cup brown sugar, 1 teaspoon baking powder, ⅛ teaspoon salt, ½ teaspoon ground cinnamon
Stir in the melted butter to form crumbles. Set aside.
½ cup butter
In a large bowl, toss together the apples, sugar, lemon juice, cornstarch, and apple pie spice.
7 cups peeled and thinly sliced baking apples, ⅓-½ cup granulated sugar, 1 tablespoon fresh lemon juice, 2 tablespoons cornstarch, 1 ½ teaspoons apple pie spice
Pour the apples into an 8x11-inch baking dish and spread into an even layer.
Drop the crumble mixture evenly over the apples.
Bake for about 40-50 minutes, or until bubbling and golden brown on top. I check the crumble at about 25-30 minutes to make sure it isn't browning too quickly. If it is, tent with aluminum foil.
Let it cool in the pan for about 15 minutes before serving.
Notes
Brown sugar: Feel free to substitute dark brown sugar in this recipe. If you use dark brown sugar, be sure to check how quickly the topping is browning and tent with foil if necessary.
Salt: If using unsalted butter, increase the salt to 1/4 teaspoon.
Butter: I use salted butter in this recipe.
Apples: I like to use a combination of baking apples for the best flavor. I like use tart Granny Smith and a sweeter apple like Pink Lady apples for more depth of apple flavor.
Sugar: Feel free to adjust the amount of sugar depending on how sweet your apples are and how sweet you like your desserts to be.
Apple pie spice: I like to use apple pie spice blend because it has more flavor than just using cinnamon. You can substitute cinnamon if you prefer.