This recipe is from the book ‘Rainbow Bakes’ by Mima Sinclair!

Before you say “this one’s too hard I can’t make it” think again. This gorgeous petal effect is much simpler to achieve than you’d imagine.

Recipe taken from ‘Rainbow Bakes’ by Mima Sinclair. Published by Kyle Books. Photography by Danielle Wood. Buy the book HERE.

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Serves 18

12oz/1½ cups/3 sticks unsalted butter, softened, plus extra for greasing
12oz/1¾ cups superfine sugar
6 large eggs
12oz/2⅔ cups all-purpose flour
2 ½ teaspoons baking powder
1 teaspoon fine salt
1 teaspoon vanilla extract
4 tablespoons whole milk

For the buttercream:
27oz/3¼ cups/6¾ sticks unsalted butter, softened
53oz/10½ cups powdered sugar, sifted
1 teaspoon vanilla extract
food coloring pastes (purple, blue, green, yellow, orange, and pink)

You will need:
6 disposable pastry bags

  1. Preheat the oven to 350°F. Grease and line three 8-inch round cake pans with parchment paper.
  2. Using an electric hand mixer, beat the butter and superfine sugar together in a large bowl until light and fluffy. Add the eggs, one at a time, beating well after each addition. Sift in the flour, baking powder, and salt and fold through evenly with a large spoon. Stir in the vanilla extract and milk until combined.
  3. Divide the mixture between the prepared pans, spreading evenly. Bake for 20 to 25 minutes, or until a skewer inserted into the center comes out clean. Let cool in the pans for 5 minutes, then turn out onto a wire rack and let cool completely before cutting each cake in half horizontally.
  4. Meanwhile, for the buttercream, beat the butter, powdered sugar, and vanilla extract together in a large bowl until light and fluffy. Divide between six smaller bowls and color each portion with a different food coloring paste. Once the cake layers are cold, sandwich them together using a few tablespoons of each different colored buttercream between each layer, then coat the cake completely with a thin layer of yellow buttercream to catch all the crumbs.
  5. Using a ruler, measure the height of your cake, then using a toothpick, mark the mid-height point all the way round. Chill the cake in the refrigerator for 1 hour.
  6. Spoon each of the remaining colored buttercreams into a separate pastry bag and snip 1/2-inch holes off the tips. Line up the bags in the order in which you want to pipe the colors, then using the marked center guideline, pipe rows of dots onto the cake—three above the line and three below. Then, use the back of a teaspoon to spread each dot of icing from the center to the right. Clean the spoon between each use.
  7. Continue with your next row of dots, but move the colors all down one position, checking often to make sure your lines are vertical. Continue in this way with all the remaining colored buttercreams but don’t spread the final row of dots. 8. Pipe a circle of dots around the outer top edge of the cake. Spread these dots as before, then continue to the center, reducing the amount of dots when it gets tight. Finish with one dot in the center.


I used americolor “electric” gels to achieve these gorgeous bright shades.

Photography by Danielle Wood

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