Pre-heat your oven to 425 degrees F.
Unroll 1 refrigerated pie crust onto work surface. Use a 3-inch cookie cutter to cut out 12 rounds.
Spray a muffin tin with non-stick cooking spray. Place each round into the bottom of a muffin cup. The dough should just start to slightly go up the side of the muffin cup. In a large bowl, combine finely chopped apples with 3 tablespoons sugar, 1 tablespoon all-purpose flour, 3/4 teaspoon cinnamon and 1 teaspoon lemon juice. Divide this apple mixture evenly among the 12 mini pies. With your food processor, a fork, or using your fingers, combine all of the ingredients for the streusel topping until crumbly. Divide this mixture evenly among the 12 mini pies. Bake for 18-20 minutes or until the tops are golden brown.
Allow the mini pies to cool for 15-20 minutes before carefully removing them from the pan.
Top with whipped cream and enjoy!