1. In a large bowl, whisk together gluten-free flour blend and almond flour. Add cold cubed butter and cut it into the flour using a pastry cutter or fingertips until coarse crumbs form with some pea-sized pieces remaining.

2. Sprinkle 4 tablespoons ice water over the mixture. Toss gently until dough begins to come together. Add more water if needed, 1 tablespoon at a time. Form into a ball without overworking.

3. Flatten dough into a disc, wrap tightly in plastic wrap, and chill for at least 30 minutes.

4. Peel, core, and dice apples. In a bowl, combine apples with brown sugar, cinnamon, and lemon juice. Let sit 15–20 minutes to macerate.

5. Preheat oven to 375°F (190°C). Roll out chilled dough on a lightly floured surface to ⅛-inch thickness. Cut circles to fit muffin tin cups.

6. Press dough circles into muffin tin cups and fill each with the apple mixture, leaving extra liquid behind.

7. Cover with full tops or lattice strips. Brush tops with beaten egg wash.

8. Bake for 20–25 minutes or until golden brown and bubbly. Cool 10 minutes in tin, then transfer to a wire rack to finish cooling.