This intricate petal design looks difficult to master, but it's actually a breeze! Try your hand at this frosting technique and use it for years (and cakes!) to come.
Rainbow Petal Sheet Cake
- Prep Time 1 hr 20 min
- Total 3 hr 30 min
- Servings 12
- Ingredients 7
Ingredients
Cake
- 1 box yellow cake mix with pudding
- Water, oil and eggs called for on cake mix box
Frosting
- 1 1/2 cups butter, softened
- 5 cups powdered sugar
- 2 teaspoons vanilla
- 2 to 4 tablespoons milk
- Blue, purple, green and orange gel food color
Instructions
-
Step1Heat oven to 350°F (325°F for dark or nonstick pans). Grease bottom only of 1 (13x9-inch) pan. Make cake mix as directed on box using water, oil and eggs.
-
Step2Bake 28 to 32 minutes or until a toothpick inserted in center comes out clean. Cool 10 minutes in pan; remove from pan to cooling rack. Cook completely, about 1 hour.
-
Step3Meanwhile, beat butter with an electric mixer on low speed until creamy. Beat in the powdered sugar, 1 cup at a time, until smooth. Add vanilla and milk, 2 tablespoons at a time until well combined. If frosting is too thick, beat in more milk.
-
Step4Use 1/2 cup frosting to frost a thin layer over entire cake. Divide remaining frosting into four bowls (about 3/4 cup frosting in each bowl). Mix blue, purple, green and orange food color, one into each bowl, until desired hue is reached.
-
Step5Place each color in individual resealable food-storage plastic bag. Cut 1/2 inch off one corner of each bag. Pipe a dot of blue frosting and use back of teaspoon to pull frosting slightly. Repeat with remaining colors, alternating colors as you cover cake, slightly overlapping dots of frosting.
Nutrition
650
Calories
35g
Total Fat
2g
Protein
80g
Total Carbohydrate
65g
Sugars
Nutrition Facts
Serving Size: 1 Serving
- Calories
- 650
- Calories from Fat
- 310
- Total Fat
- 35g
- 53%
- Saturated Fat
- 17g
- 86%
- Trans Fat
- 1g
- Cholesterol
- 110mg
- 36%
- Sodium
- 480mg
- 20%
- Potassium
- 45mg
- 1%
- Total Carbohydrate
- 80g
- 27%
- Dietary Fiber
- 0g
- 0%
- Sugars
- 65g
- Protein
- 2g
% Daily Value*:
- Vitamin A
- 15%
- 15%
- Vitamin C
- 0%
- 0%
- Calcium
- 8%
- 8%
- Iron
- 4%
- 4%
Exchanges:
1/2 Starch; 0 Fruit; 5 Other Carbohydrate; 0 Skim Milk; 0 Low-Fat Milk; 0 Milk; 0 Vegetable; 0 Very Lean Meat; 0 Lean Meat; 0 High-Fat Meat; 7 Fat;Carbohydrate Choice
5Tips from the Betty Crocker Kitchens
{{tipItemHeadingFormat.replace('{0}',props.index + 1)}}
© 2025 ®/TM General Mills All Rights Reserved