Make your favorite brownie mix or recipe and bake according to the temperature listed. To make the brownies thinner for stacking, bake them in a larger baking dish than the recipe calls for, and alter the baking time accordingly. Instead of an 8x8 pan that a brownie mix calls for, pour your brownie batter into a 9x13 prepared pan. If using a 9x13 pan and making brownies from scratch, use about 2/3 of the batter, and put the remaining brownie mixture in an 8x8. Remember to watch baking times closely...you don't want to over bake brownies. Use a toothpick to check the middle.Reduce baking time by about half, then watched them closely until they are done. Let them cool completely.
While the brownies are baking, make your frosting by beating the powdered sugar and softened butter together in a mixer or in a large bowl (using an electric mixer). Slowly add the half and half in until you have the right consistency--not too thick, and not too thin. Add the vanilla and salt, and beat well. I like to use salted butter, although many bakers use unsalted butter. If you use salted butter, you just need a dash of salt. With unsalted butter you'll need a but more. Add as much food coloring as you want to achieve the right shade of pink.
Cool brownies completely, then use the round biscuit cutter to cut out as many hearts as possible. Remove them, and place them on a large platter or plate. In half of the circles, use the smaller heart cookie cutter to cut out a heart in the center of the circle. Remove the smaller hearts and set them aside. (You can frost them and serve them separately!)
Frost the full circle brownies, then place the brownies with the hearts cut out on top. Sprinkle with powdered sugar!
Notes
My favorite brownie recipe: https://cafedelites.com/best-fudgy-cocoa-brownies/