Preheat the oven to 350 degrees and spray a 12x19 cookie sheet with pam spray. Cover the pan with parchment paper.
Using a large bowl, beat the butter, sugar, brown sugar, eggs, coffee, and vanilla until combined and fluffy
In a medium bowl, whisk the cocoa powder, espresso grounds, flour, cornstarch, and baking powder
Gradually beat in the dry ingredients into the wet
Spread the brownie batter onto the cookie sheet
Bake in the oven for 22-26 minutes or until a toothpick in the center comes out clean
Allow to cool completely
Using the Heart cookie cutter, cut out 12 brownie hearts and place onto a wire rack.