Preheat oven to 350°F. Unroll one pie crust and use a 2 1/2” round cookie cutter to cut circles of dough, re-rolling as needed. Spray mini muffin tins with cooking spray (I like to use the kind with flour in it) and press one round in each cavity. Repeat with second crust in box. You will get about 36. Chill until ready to fill.
Prepare brownie mix according to the package directions. Remove crusts from refrigerator and fill each cavity with 1 tablespoon brownie batter. (You’ll have some leftover. You can bake the leftover as cupcakes or in a loaf pan and use for brownie pops or just eat it with a fork.)
Bake pies for about 15 minutes, until the crust is browned. Let them cool completely before frosting.
Once cooled, a gentle urging from a butter knife will help the pies pop out of the muffin pans. Place your vanilla frosting in a sandwich baggie and cut off a teeny tiny bit of the tip. Pipe laces onto your pies and enjoy!