Preheat the Oven: Preheat your oven to 350°F (177°C). Grease a 9×13-inch baking dish with non-stick cooking spray or line it with parchment paper.
Make the Cake Base: In a large bowl, whisk together flour, sugar, cocoa powder, baking powder, and salt. Add 1 egg, ½ cup melted butter, buttermilk, and red food coloring. Mix until a dough forms. Press the dough evenly into the prepared baking dish.
Prepare the Cream Cheese Topping: In a separate bowl, beat the cream cheese with an electric mixer until smooth. Add the remaining 2 eggs, vanilla extract, and ½ cup melted butter, and mix until well combined. Slowly add confectioners’ sugar, beating until the mixture is creamy.
Bake: Pour the cream cheese mixture over the red velvet base in the baking dish. Bake for about 40 minutes, checking for doneness at the 25-minute mark. The center should remain slightly gooey but not raw, and the edges should be golden.
Cool and Serve: Let the bars cool completely before slicing them into 16 squares. Dust with powdered sugar before serving for an extra touch.