1. 1. Preheat your oven according to the instructions on the yellow cake mix box. Grease a 9×13 baking pan. In a large mixing bowl, combine the cake mix, milk, melted butter, vanilla, eggs, and egg yolk. Mix until the batter is smooth and well combined. Pour the batter into the prepared pan and bake as directed on the box, or until a toothpick inserted in the center comes out clean.

2. 2. Allow the cake to cool completely before proceeding to the next step.

3. 3. Once the cake has cooled, use a 3-inch round cookie cutter to cut the cake into individual rounds.

4. 4. In a medium bowl, beat the softened butter with a hand mixer until light and creamy. Add the vanilla, powdered sugar, and milk, and continue beating until the buttercream is smooth and fluffy.

5. 5. To assemble the Zebra Cakes, spread a generous amount of buttercream between two cake rounds, creating a sandwich. Repeat this process with all the cake rounds, using up all the buttercream.

6. 6. Melt the vanilla almond bark according to the package instructions. Carefully dip or coat each cake sandwich in the melted almond bark, ensuring an even, smooth coating. Drizzle the tops with the melted semi-sweet chocolate chips for that classic Zebra Cake look.

7. 7. Allow the coated cakes to set and harden completely before serving.