Pink Cake

For the cake

1. Preheat the oven to 325 degrees F. Coat three 8-inch cake pans with cooking spray and line the bottom and sides with parchment paper. Soak three cake baking strips in water.
2. Sieve the flour, baking powder, baking soda, and salt into the bowl of a mixer, then stir in the sugar.
3. In a separate bowl, use a whisk to combine the buttermilk, melted butter, vegetable oil, eggs, vanilla, vinegar, and pink food coloring.
4. Slowly mix the wet ingredients into the dry ingredients using a stand mixer fitted with the paddle attachment until the mixture is just combined. Be careful not to overmix your batter.
5. Pour the batter evenly between the three pans. Squeeze out the excess water from the baking strips and secure around the pans.
6. Bake for 50-55 minutes, or until the cakes are springy to touch and a toothpick comes out clean or with a few crumbs attached.
7. Let the cakes cool in the pans for 20 minutes, then carefully invert the cakes onto a cooling rack. Remove the parchment and cool completely.

For the frosting

1. Fill a pot halfway with water, and bring it to a simmer. Place a bowl of the egg whites and sugar over the pot of simmering water, and whisk to combine. Continue to heat, whisking frequently until the temperature reaches 160°F and whisk for a further 2 minutes. This makes the egg whites safe to eat by killing any bacteria that may be present.
2. Transfer the mixture to the bowl of a stand mixer fitted with the whisk attachment. Whisk on high for around 10 minutes until the mixture forms soft peaks and resembles meringue.
3. Change the mixer to the paddle attachment and mix on slow as you add the butter, a few cubes at a time.
4. To begin with the mixture will appear to be curdled, this is normal. Continue to mix and after a few minutes it will transform into a silky smooth buttercream.
5. To tint the buttercream, use a toothpick to add a small amount of food coloring at a time. Mix after each addition until you are satisfied with the color. It should be paler than the cake layers for contrast. For best results use the frosting right away.
6. Set aside 1 cup of frosting to pipe the rosettes.

For assembly

1. Trim the top and bottom off the cakes with a large, serrated knife or cake leveler to remove the crust and create flat, even layers.
2. Attach an 8-inch cake board onto a 10-inch cake board with a little buttercream. Place onto a cake turntable and attach one cake layer onto it with a little buttercream. Pipe a thin layer of frosting over the cake layer, smooth with a cake scraper if necessary, then add the second layer on top. Repeat with more frosting and add the third layer.
3. Trim the sides of the assembled cake with a serrated knife to create a flat surface.
4. Use an offset spatula to apply a thin crumb coat of buttercream. Chill the cake for 15-20 minutes until set.
5. Add more buttercream to the top and sides of the cake and use a cake scraper to create a smooth top and sides. Chilling the cake at intervals makes this process easier.
6. Press sprinkles into the side of the cake around the bottom edge going up around halfway. Running a cake smoother around the base of the cake over the sprinkles helps to flatten them into the sides of the cake. Chill until firm.
7. Place a large, closed star nozzle into a large piping bag and fill with the reserved frosting.
8. Pipe 12 rosettes around the top edge of the cake.
9. Sprinkle a few sprinkles onto each rosette.
10. Transfer the cake to a cake stand to serve.