Layered Grapefruit Cake

Preheat oven to 325°F (170°C). Spray a 9-inch springform pan with baking spray with flour. Line bottom of pan with parchment paper.

In the bowl of a stand mixer fitted with the paddle attachment, beat butter, sugar, and grapefruit zest at medium speed until fluffy, 3 to 4 minutes, stopping to scrape sides of bowl. Add eggs, one at a time, beating well after each addition. Beat in grapefruit juice and vanilla. (Mixture may look slightly curdled at this point, but batter will come together.)

In a medium bowl, whisk together flour, baking powder, and salt. In a small bowl, stir together milk and food coloring*. With mixer on low speed, gradually add flour mixture to butter mixture alternately with milk mixture, beating until combined after each addition and stopping to scrape sides of bowl. Spoon batter into prepared pan, smoothing top with a small offset spatula.

Bake for 35 minutes; cover with foil, and bake until a wooden pick inserted in center comes out clean, 5 to 7 minutes more. Let cool in pan for 5 minutes. Remove sides of pan; let cake cool completely on base of pan on a wire rack.

Using a serrated knife, level cooled cake. Wrap a 30×4-inch strip of parchment paper around top half of cake, fitting it flush around sides to form a collar; securely staple together. (You can use more than one strip of parchment, if necessary.) Replace sides of pan.

In a medium bowl, stir together 2¼ cups (330 grams) Vanilla Whipped Topping and Campari until well combined. Transfer Campari topping to a pastry bag, and cut a ½-inch opening in tip; pipe evenly onto cake. Using a small offset spatula, spread into an even layer. Using a paper towel, clean any smears of Campari topping off parchment. Freeze for 25 minutes.

Whisk remaining Vanilla Whipped Topping until thickened, if necessary; spoon onto frozen Campari topping, smoothing into an even layer and swirling as desired using the back of a spoon. Loosely cover and refrigerate for at least 4 hours or up to overnight.

Carefully remove sides of pan and parchment. Smooth sides and patch any holes in topping, if necessary. Serve immediately.

In the bowl of a stand mixer fitted with the whisk attachment, beat cream cheese and sugar at medium speed until smooth and well combined, stopping to scrape sides of bowl. Reduce mixer speed to medium-low; slowly add one-third of cold cream, beating until smooth and stopping frequently to scrape sides of bowl. With mixer on medium speed, gradually add vanilla and remaining cold cream, beating until thickened and medium peaks form. (Do not overmix.)