Ingredients:

  • 1 cup (225g) unsalted butter, room temperature
  • 3/4 cup (90g) powdered sugar
  • 1 tsp (5ml) pure vanilla extract
  • 2 cups (250g) all-purpose flour
  • 1/2 cup (45g) dutch-processed cocoa powder
  • 1/2 tsp (3g) fine sea salt
  • 2 tbsp (16g) cornstarch
  • 6 oz (170g) dark chocolate (60% cacao), chopped
  • 1/2 cup (120ml) heavy cream
  • 1 tsp (5ml) light corn syrup
  • 1 tbsp (14g) unsalted butter, cold

Instructions:

  1. Cream the 1 cup of room temperature butter and 3/4 cup powdered sugar until pale and fluffy. This should take about 3 to 4 minutes on medium speed.
  2. Whisk together the 2 cups flour, 1/2 cup cocoa, salt, and 2 tbsp cornstarch. Add this to the butter mixture on low speed until just combined and no white streaks remain.
  3. Roll the dough between two sheets of parchment paper to 1/4-inch thickness.
  4. Cut 24 large hearts using a 2-inch cutter. On 24 of those hearts, use a 1-inch cutter to remove the center, creating a window for the sandwich top if making sandwich cookies.
  5. Bake the cookies at 350°F (175°C) for 12 minutes until set but not browned. Allow to cool completely on a wire rack.
  6. Prepare the ganache: Heat heavy cream and corn syrup until simmering, then pour over chopped dark chocolate. Let sit undisturbed for 5 minutes, then whisk until glossy. Stir in the cold tablespoon of butter.
  7. Transfer ganache to a piping bag and pipe a layer onto the solid heart bases. Top with the windowed heart cookies and press gently to set.