Description
This Surprise Rainbow Bundt Cake is a delightful and visually stunning dessert featuring vibrant rainbow-colored batter hidden inside a moist and fluffy white bundt cake. The combination of all-purpose and cake flours with butter, coconut oil, and buttermilk creates a tender crumb, while the colored layers inside add a fun and magical surprise for any occasion.
Ingredients
Scale
Dry Ingredients
- 260g all purpose flour
- 100g cake flour
- 2 tsps baking powder
- 1 tsp fine sea salt
Wet Ingredients
- 226g unsalted butter, softened
- 75g coconut oil
- 400g fine, granulated sugar
- 2 tsps pure vanilla extract
- 1 tsp imitation vanilla
- 4 large egg whites
- 240g buttermilk
Coloring
- Gel food coloring: red, yellow, green, blue, purple
Instructions
- Preheat and Prepare Pan: Preheat your oven to 350°F (175°C). Thoroughly butter and flour a large bundt pan to prevent sticking.
- Sift Flours: Sift together the all-purpose flour and cake flour into a bowl and set aside. This ensures the flours are aerated and lump-free.
- Cream Fats and Sugar: In a large mixing bowl, cream together the softened butter, coconut oil, granulated sugar, sea salt, pure vanilla extract, imitation vanilla, and baking powder for a full 5 minutes until the mixture is very light and fluffy. This step incorporates air to create a tender cake texture.
- Add Egg Whites: With the mixer running on medium speed, add the egg whites one at a time, ensuring each is fully incorporated before adding the next. This helps to maintain volume and lightness in the batter.
- Combine Flour and Buttermilk: Add the sifted flour mixture to the bowl. Turn the mixer on low and slowly drizzle in the buttermilk. Mix only until combined to avoid overworking the batter.
- Divide and Color Batter: Divide the batter into 5 separate bowls, each with about 1/3 cup of batter. Add gel food coloring—red, yellow, green, blue, and purple—to each bowl and stir gently to combine and create vibrant batters.
- Fill Bundt Pan Base: Pour and spread more than 2/3 of the remaining plain batter evenly into the prepared bundt pan, leaving some batter for the top layer and the colored sections.
- Pipe Colored Batter: Transfer each colored batter into separate piping bags and snip off the tips. Use the back of a teaspoon to create a circular space or moat in the batter where you’ll pipe the colors.
- Create Rainbow Pattern: Pipe a red circle into the moat first, smoothing it with the back of a spoon so it’s wide but leaves a white border on the inner and outer edges. Continue with yellow, green, blue, and then purple, decreasing the width of each color band. This forms the hidden rainbow swirl inside the cake.
- Top with Remaining Batter: Spoon the remaining plain batter on top of the colored swirl and gently smooth with an offset spatula to cover the rainbow carefully without disturbing it.
- Bake the Cake: Bake in the preheated oven for about 45 minutes. Check for doneness at 40 minutes by pressing the cake lightly; it should spring back when done.
- Cool: Let the cake cool in the pan for approximately 15 minutes before carefully inverting it onto a cooling rack to cool completely before serving.
Notes
- This cake features a hidden rainbow surprise that appears only when sliced, perfect for celebrations or a fun dessert.
- Using gel food coloring gives the most vibrant colors without altering the batter consistency.
- Ensure the bundt pan is well greased to avoid sticking and tearing the delicate cake design.
- The cake is light yet moist thanks to the combination of butter, coconut oil, and buttermilk.
- Allow the cake to cool sufficiently before slicing to preserve the integrity of the rainbow pattern.
Nutrition
- Serving Size: 1 slice (1/12th of cake)
- Calories: 360 kcal
- Sugar: 28 g
- Sodium: 150 mg
- Fat: 22 g
- Saturated Fat: 12 g
- Unsaturated Fat: 8 g
- Trans Fat: 0.5 g
- Carbohydrates: 35 g
- Fiber: 1 g
- Protein: 4 g
- Cholesterol: 70 mg
