Red Velvet Unicorn Cake

My friend requested a red velvet cake. So I looked for recipes online and settled on following the one from Sally's Baking Addiction. I cut the red food color by half so my cake is not so brightly red, but hopefully healthier. The recipe is good for a 2-3 layers 8-9" cake, depends on the height desired. I actually doubled the recipe and split it into a 4 layer 8" round cake and a 2 layer 9" round cake.

Ingredients

Cake flour - 3 cups
Baking soda - 1 tsp
Unsweetened cocoa powder - 2 TBSP
Salt - 1/2 tsp
Unsalted butter - 1/2 cup, softened to room temperature
Sugar - 2 cups
Oil - 1 cup
Large eggs - 4, room temperature and separated
Pure vanilla extract - 1 and 1/2 TBSP
Distilled white vinegar - 1 tsp
Buttermilk - 1 cup, room temperature (can DIY by mixing 1 TBSP fresh lemon juice with 1 cup milk, and let it sit for 5 minutes)
liquid red food coloring - 0.5 to 1 oz, or use gel red color
Cream Cheese Frosting for icing
Swiss Meringue Buttercream for flower decoration because cream cheese frosting seems too soft to pipe details

Steps

1. Preheat oven to 350°F. Spray or lightly butter cake pans, could be 2-3 8" or 9" cake pans, depends on how many layer and how tall the cake will be.
2. Whisk the flour, baking soda, cocoa powder, and salt together in a large bowl. Set aside.
3. Using a handheld or stand mixer fitted with a paddle attachment, beat the butter and sugar together on high speed until smooth and creamy. Add the oil and beat on high for 2 minutes.
4. Add egg yolks and the vanilla. (Set the egg whites aside.) Beat on medium high speed until combined. Beat in the vinegar and the food coloring until you reach your desired color.

5. With the mixer on low speed, add the dry ingredients in three additions alternating with the buttermilk.
6. Vigorously whisk or beat the 4 egg whites until thick and foamy, about 3 minutes. Fold into cake batter with a rubber spatula or wooden spoon. The batter will be silky and slightly thick.

7. Pour batter into cake pans filling 2/3 or less full. Bake for 20-35 minutes or until the tops of the cakes spring back when gently touched and a toothpick inserted in the center comes out clean.

8. Remove from the oven and allow cakes to cool completely in the pans set on a wire rack.

9. For the unicorn cake, I have made the horn and ears with fondant two days ahead. The horn is made from white fondant, and painted with golden edible glitter.  The ears are painted pink inside with diluted pink gel color.

10. Stack up the layers and decorate. The cream cheese frosting is soft at room temperature and the layers slips, so I inserted a wooden dowel in the middle.

Make ahead tip:
The cake layers can be baked, cooled, and covered tightly at room temperature overnight. Likewise, the frosting can be prepared then covered and refrigerated overnight. Let it sit at room temperature to slightly soften for 10 minutes before assembling and frosting. Frosted cake can be frozen up to 2-3 months. Thaw overnight in the refrigerator and bring to room temperature before serving.