Preheat your oven to 375°F then spray nonstick spray in each cavity of your muffin tin. You can also add a strip of parchment paper to make it easier to pull them out once they're done.
In a mixing bowl, combine the diced apples, granulated sugar, ground cinnamon, ground nutmeg, melted butter, and lemon juice. Toss until the apples are well coated with the sugar and spices. Set aside.
Roll out one of the pie crusts on a lightly floured surface. Use a 3.4-4 inch round cookie cutter or a glass to cut out circles that are slightly larger than the openings of your standard muffin tin. You should be able to get about 6 circles from each pie crust. Repeat with the remaining pie crust.
1 package of store-bought refrigerated pie crusts
Carefully press each pie crust circle into the cups of your muffin tin, making sure to mold them to the shape of the cups. Trim any excess crust hanging over the edges. Make sure that the parchment paper is still poking out of the sides. Put aside for later.
In a separate bowl, prepare the cinnamon streusel topping. Combine the all-purpose flour, brown sugar, cold cubed butter, ground cinnamon, and a pinch of salt. Use a pastry cutter or your fingers to blend the mixture until it resembles coarse crumbs.
1/2 cup all-purpose flour, 1/2 cup brown sugar, 1/4 cup butter, 1 teaspoon ground cinnamon, 1/2 teaspoon salt
Fill each crust with the prepared apple filling, then sprinkle the cinnamon streusel topping over them.
Place the muffin tin in the preheated oven and bake for about 30 minutes, and until the streusel is golden and crispy and the filling is bubbling.
Remove the mini apple pies from the oven and allow them to cool in the tin for a few minutes. Then, carefully transfer them to a wire rack to cool completely.
Once the mini apple pies with cinnamon streusel have cooled, you can serve them as is, with a dusting of powdered sugar, or with a scoop of vanilla ice cream or a drizzle of caramel sauce.
powdered sugar
Notes
The parchment strip trick: before you press in the pie crusts, cut twelve small strips of parchment paper, about 4 inches (10 cm) long and 1 inch wide. Lay one across each cavity of the muffin tin with both ends sticking up over the rim, then press the crust in on top of it and make sure the ends are still poking out. When the pies are baked and cooled, grab both ends and lift the pie straight out. No knife around the edges, no prying, nothing breaking. This is the tip I get the most messages about, and it's the difference between twelve perfect mini pies and six perfect ones plus a lot of patching.Freezing: freeze them baked. Cool completely, freeze in an airtight container with parchment between layers for up to 2 months, and reheat from frozen at 350°F for 15 to 20 minutes. Don't thaw first.