• Preheat oven to 425 F. Lightly spray muffin tin cups (or mini tart pans) with cooking spray.

Make the Apple Filling

• Melt butter in a heavy bottom saucepan over medium-high heat.
• Add flour and stir quickly until combined.
• Add 3 tablespoons water and sugar and mix well. Cook for approximately 5 minutes until it becomes a caramel sauce.
• Remove from heat and allow it to cool.
• Meanwhile, dice the apple and toss with ground cinnamon.
• Combine caramel sauce and apples, mix well.

Prepare the Pies

• Cut 12 circles from the pie dough using a 3.5-inch round biscuit cutter or cookie cutter.
• Tuck the pie dough circles snugly into the cups.
• Divide the apple filling evenly among the cups. Fill them full, but flush, not mounded.
• Cut the rest of the pie dough into thin strips. Layer the strips on top of the mini pies by weaving over and under and alternating each one.
• In a small bowl, whisk the egg and a teaspoon of water until frothy.
• Brush the tops with the egg wash. If you would like to add handles, please see "notes" below.
• Bake for 20-25 minutes, until light golden brown and the apple filling is bubbly.
• Allow pies to cool in pan on a cooling rack for 10-15 minutes. Remove from tart pans or muffin tin and cool completely on wire rack.