Preheat your oven to 425°F (220°C) and get ready for some cozy baking vibes. Lightly grease your muffin tin or line it with paper cups, this makes it so much easier to pop the mini pies out later.
Take your pie crust (homemade or pre-rolled) and cut out rounds with a 4-inch cutter, a cup, or anything handy. Gently press each round into the muffin tin cups. If the dough tears a bit, no worries, patch it with a pinch of leftover dough. Keep rolling out scraps until all 12 cups are ready for their filling.
In a mixing bowl, toss your diced Honeycrisp apples with light brown sugar, cornstarch, vanilla, cinnamon, and a tiny pinch of nutmeg. Make sure every piece is coated evenly.
Fill each crust with the apple mixture, leaving a small gap at the top. Don’t squish it down too much, this keeps the apples tender and prevents spills while baking.
For the crumb topping, mix flour and light brown sugar in a small bowl, then drizzle in melted salted butter and stir until soft, crumbly clusters form. Sprinkle the topping over each pie generously.
Bake for 18–20 minutes, until the tops are golden and the apples peek through just a little. If your oven runs hot, check earlier, the sugar can brown quickly.
Let the pies cool in the tin for about 20 minutes so they set properly, then carefully loosen the edges and move them to a wire rack to finish cooling.