- Cake:
- 1 (18.25 ounce) package white cake mix
- 1 (3 ounce) package instant white chocolate pudding mix
- 3/4 cup milk
- 1/2 cup vegetable oil
- 5 tablespoons Key lime juice
- 1 tablespoon Key lime zest
- 4 eggs
- Frosting:
- 1 (16 ounce) container lemon frosting
- 1/4 cup grated white chocolate
- 1 tablespoon Key lime zest
- 1 tablespoon Key lime juice
- Preheat oven to 350 degrees F (175 degrees C). Grease and flour a 9×13-inch baking dish.
- Mix cake mix and pudding mix together in a bowl. Beat milk, vegetable oil, 5 tablespoons Key lime juice, and 1 tablespoon Key lime zest into cake mix mixture just until batter is smooth. Beat eggs, 1 at a time, into batter, beating until each egg is incorporated before adding the next. Pour batter into the prepared baking dish.
- Bake in the preheated oven until a toothpick inserted in the center of the cake comes out clean, about 45 minutes. Cool cake to room temperature.
- Mix lemon frosting, white chocolate, 1 tablespoon Key lime zest, and 1 tablespoon Key lime juice together in a bowl. Spread frosting over cake.