Flourless Brownies with Peanut Butter Frosting are easy to make and irresistible! A fudgy brownie is topped with whipped peanut butter buttercream frosting to create a sweet treat that everyone will love.
To make the brownies, preheat oven to 350 degrees. Line an 8x8 square pan with foil and spray lightly with baking spray; set aside.
In a small saucepan set over low heat, melt the butter. Stir in the sugar until incorporated. Add the chopped chocolate, stirring until smooth. Remove from heat and add the eggs, one at a time. Add the vanilla extract and stir until incorporated.
While mixing, slowly add the cocoa powder, cornstarch and salt. Using a hand mixer on high speed, beat the batter until smooth and shiny, 1 to 2 minutes. (You can also do it by hand, beating vigorously.)
Pour the batter into the prepared pan and bake for 25 to 30 minutes or until the brownies are set in the center. Remove from oven and let cool in the pan for at least one hour.
To prepare the frosting, in a bowl of a stand mixer fitted with the paddle attachment, add the butter and beat on medium speed for one minute. Add the peanut butter and beat until combined. Slowly add the confectioners' sugar and salt. Mix until combined, scraping down the sides of the bowl as needed. Add the heavy cream and mix until light and fluffy, about 2 to 3 minutes. Spread the frosting over the brownies, remove from pan and slice before serving.