Preheat the oven to 375 degrees.

Combine the dry cake mix, the dry pistachio pudding mix, butter, and eggs in a stand mixer, then mix well.

Roll the dough into about 1” balls using a small cookie scoop.

Combine the powdered sugar and cornstarch in a small bowl.

Roll each cookie dough ball in the powdered sugar and cornstarch mixture.

Place the balls on a silicone mat lined baking sheet and bake cookies for 8-10 minutes or until the cookies are lightly brown on the bottom and still soft to the touch on top.

Remove the cookies from the oven and immediately press a candy heart gently into the corner of each.

Let the cookies rest for 1-2 minutes, then transfer them to a wire rack.