QL Rainbow Cake with Natural Coloring

We’d like to share with you our very own wholesome twist of the classic rainbow cake recipe, alive with vibrant colours derived from completely natural ingredients including carrot, red yeast, baby spinach, blue pea flower and blackberries. This visually arresting cake is coated with a thin layer of mouth-watering lemony Swiss meringue buttercream.

Be sure to use QL Omega eggs for an even bigger heath boost. They have 50% less cholesterol than ordinary eggs and taste excellent. You can pick up QL Omega eggs from most good supermarkets and hypermarkets.

Wait no more! Get ready to impress your guests this festive season, even more when they find out that it is completely free from any artificial food colourings.


Preparation time: 1 hour
Cooking time: 45 minutes
Servings: 9


For cake:
390 gplain flour
4 tspbaking powder
1/2 tspsalt
250 gunsalted butter
240 gsugar
2QL Omega egg whites
2 tspvanilla essence
350 mlfresh milk
For colouring:
Orange½ stalk pure carrot juice
Red2tsp red yeast powder
Green½ cup pure baby spinach juice
Blue½ cup blue pea flower soaked in ¼ cup hot water
Purple¼ cup blackberries juice
For frosting (Lemony Swiss Meringue Buttercream):
10QL Omega egg whites
300 gsugar
460 gunsalted butter
3 tbsplemon juice


  1. To prepare the cake, grease and line a 9 inch round cake tin. Preheat oven to 160C.
  2. Mix together flour, baking powder and salt; set aside.
  3. Cream together butter and sugar. Slowly add QL Omega egg whites and mix until well combined. Add vanilla. Add flour mixture and milk in two alternating additions and mix until well combined.
  4. Divide batter evenly between 6 medium bowls. Add and mix enough of each colour of natural food colouring to each bowl. Transfer each colour to an individual cake pan and bake for 15 minutes.
  5. Remove cakes from oven and transfer to a wire rack; let cool for 10 minutes.
  6. Trim tops of cakes to make level. Place the purple layer on the cake board.
  7. On a lazy Susan, spread 1 cup buttercream filling over the first layer with a small offset spatula so it extends just beyond edges. Repeat process with blue, green, red, orange and lastly the neutral colour layer. Using an offset spatula, cover the top and sides with a thin layer of frosting
  8. Refrigerate until set, about 30 minutes.
  9. Lastly, cover cake again with remaining frosting.
  10. To prepare the frosting, place QL Omega egg whites and sugar in a small saucepan over medium heat, whisking constantly until sugar is completely dissolved. Transfer to the bowl and whisk until mixture is room temperature. Slowly add in butterand mix well.
  11. Switch to paddle attachment and increase speed to high and beat until buttercream comes together, add in lemon juice and mix well.


QL Omega & QL Deli Fresh eggs are available at major hypermarkets and supermarkets. For more information on QL Eggs, click here.


About the author