Description
A soft, fluffy homemade vanilla cake filled with colorful rainbow sprinkles and topped with rich, creamy vanilla buttercream. Perfect for birthdays, celebrations, or anytime you want a festive homemade dessert.
Ingredients
1 cup all-purpose flour
3/4 cup granulated sugar
2 teaspoons baking powder
Pinch of salt
1 large egg
1/2 cup buttermilk
1/3 cup sour cream
1/4 cup canola or vegetable oil
2 teaspoons vanilla extract (for cake)
1/2 cup rainbow sprinkles (for cake)
1/2 cup unsalted butter, softened
2 teaspoons vanilla extract (for buttercream)
Pinch of salt (for buttercream)
1 1/2 to 2 cups confectioners’ sugar
1/3 cup rainbow sprinkles (for topping)
Instructions
- Preheat the oven to 350°F (175°C). Line and lightly grease an 8-inch square baking pan.
- Whisk together the flour, sugar, baking powder, and salt in a large mixing bowl.
- In a separate bowl, whisk together the egg, buttermilk, sour cream, oil, and vanilla extract until smooth.
- Pour the wet ingredients into the dry ingredients and stir gently until just combined. Do not overmix.
- Fold in the rainbow sprinkles carefully to prevent the colors from bleeding.
- Spread the batter evenly into the prepared pan.
- Bake for about 30 minutes, or until a toothpick inserted into the center comes out clean or with a few moist crumbs.
- Cool the cake completely on a wire rack.
- To make the buttercream, beat the softened butter with the vanilla extract and salt until smooth. Gradually beat in the confectioners’ sugar until light and fluffy.
- Spread the buttercream evenly over the cooled cake and top with the remaining rainbow sprinkles before slicing and serving.
Notes
Use rainbow jimmies for the best color retention during baking.
Substitute buttermilk by adding a little vinegar or lemon juice to regular milk and letting it sit for a few minutes.
Add white chocolate chips for extra richness.
Swap vanilla extract for almond extract for a different flavor.
Bake as cupcakes for 18 to 22 minutes.
Store covered at room temperature for up to 2 days or refrigerate for up to 5 days.
Freeze individual slices for up to 3 months and thaw overnight in the refrigerator.
Do not microwave the frosted cake, as the buttercream may melt.
- Prep Time: 10 minutes
- Cook Time: 30 minutes
- Category: Dessert
- Method: Bake
- Cuisine: American
Nutrition
- Serving Size: 1 slice
- Calories: 439 kcal
- Sugar: 39 g
- Sodium: 180 mg
- Fat: 20 g
- Saturated Fat: 9 g
- Unsaturated Fat: 10 g
- Trans Fat: 0 g
- Carbohydrates: 61 g
- Fiber: 1 g
- Protein: 4 g
- Cholesterol: 55 mg
