How to Make Box Cake Better (White Cake Mix)
Find out why people have called this easy white cake “the best cake they have EVER had”! Be prepared for tons of compliments when you make this! Follow my easy hacks to make a box cake taste homemade and you’ll be shocked how good it is!
Servings: 20 servings
Ingredients
Cake
- 15.25 oz white cake mix
- ½ cup (60g) all-purpose flour
- ½ cup (99g) granulated sugar
- ¾ tsp salt
- 1 large egg
- 2 large egg whites
- 1 cup (236ml) whole milk skim or 2% is fine
- ⅓ cup (76g) sour cream
- ¼ cup (50g) oil vegetable oil, olive oil or avocado oil
- 1 tsp vanilla extract
Vanilla Buttercream
- 1 cup (226g) unsalted butter, room temperature 2 sticks
- 3-4 cups (339g-454g) powdered sugar
- 1 tsp vanilla extract
- 1 Tbsp milk if frosting becomes too thick
Instructions
Cake
- If your box of cake mix is NOT 15.25 oz, do not proceed. This recipe was updated in February 2026 to address feedback and improve the overall texture, creating a lighter, more tender cake.
- Preheat the oven to 350º F.
- In a large mixing bowl combine the egg whites, whole egg, milk, sour cream, oil and vanilla extract. Whisk to combine, 30 seconds.1 large egg, 2 large egg whites, 1 cup (236ml) whole milk, 1/3 cup (76g) sour cream, 1 tsp vanilla extract, 1/4 cup (50g) oil
- Add in the dry cake mix, flour, granulated sugar and salt. Beat with an electric mixer for 30 seconds.15.25 oz white cake mix, 1/2 cup (99g) granulated sugar, 1/2 cup (60g) all-purpose flour, 3/4 tsp salt
- Spray a 9x13 inch pan with non-stick cooking spray. Pour the batter into the pan and bake for 27-37 minutes or until a toothpick inserted in the center of the cake comes out clean. Allow the cake to cool completely before adding frosting.
Vanilla Buttercream
- In a mixing bowl, combine the butter and vanilla extract, beat using an electric mixer until fluffy. Begin to add the powdered sugar, about 1 cup at a time, mixing by hand. Continue adding powdered sugar until the frosting no longer looks wet and tastes good to you. Then I use my electric mixer one last time to make sure the powdered sugar is really incorporated and ready to go. If the frosting becomes too thick, add a dash of milk.1 cup (226g) unsalted butter, room temperature, 3-4 cups (339g-454g) powdered sugar, 1 tsp vanilla extract, 1 Tbsp milk
- Spread the frosting on top of the cooled cake, add sprinkles if desired.
Video
Notes
Pair it with chocolate frosting.
Nutrition
Calories: 396kcal | Carbohydrates: 64g | Protein: 3g | Fat: 15g | Saturated Fat: 7g | Polyunsaturated Fat: 1g | Monounsaturated Fat: 5g | Trans Fat: 0.5g | Cholesterol: 39mg | Sodium: 254mg | Potassium: 57mg | Fiber: 0.4g | Sugar: 51g | Vitamin A: 354IU | Vitamin C: 0.04mg | Calcium: 73mg | Iron: 1mg