How to Make It
Prepare the Brownies: Preheat oven to 350°F. Line bottom and sides of a 9-inch square baking pan with aluminum foil, allowing 2 to 3 inches to extend over sides; lightly grease (with cooking spray) foil.
Microwave chocolate and butter in a large microwavable bowl on HIGH until melted and smooth, 1 1/2 to 2 minutes, stirring at 30-second intervals. Whisk in sugar; add eggs, 1 at a time, whisking just until blended after each addition.
Whisk together flour, baking powder, and salt in a medium bowl. Gently stir flour mixture, food coloring, and vanilla into chocolate mixture, stirring just until well incorporated.
Pour batter into prepared pan. Bake in preheated oven until a wooden pick inserted in center comes out with a few moist crumbs, 25 to 30 minutes. Transfer to a wire rack, and let cool completely, about 2 hours.
While Brownies cool, prepare the Cream Cheese Frosting: Beat cream cheese and softened butter in bowl of a heavy-duty stand mixer fitted with paddle attachment on medium speed until creamy. Reduce speed to low, and gradually beat in powdered sugar until blended. Beat in vanilla. Increase speed to medium-high, and beat until light and fluffy, about 1 to 2 minutes. Cut brownies into squares. Using a piping bag fitted with a large star tip, pipe frosting on top of brownies. Or spread frosting over brownies.