Preheat oven to 180c.
Beat together the sugar and butter until light and creamy.
Add egg yolks, flour, pureed beetroot and vanilla, and beat until smooth.
In a clean bowl, whisk the egg whites until fairly stiff.
Take a large spoonful of the egg whites and beat into the cupcake mix to loosen it a little.
Using a metal spoon, fold the remaining egg white gently through the mix, taking care not to over beat.
Spoon mix into 15 large cupcake cases and bake for around 20 mins until firm to touch.
Cool on a wire rack.
To make the icing
Beat the icing sugar and butter together.
Add a few drops of rose flower water and beetroot juice to colour.
Spread or pipe onto cakes and decorate with glitter.
Bake it Better for Great Ormond Street Hospital
Wendi Peters has provided this recipe to support Great Ormond Street Hospital's Bake it Better - an annual event to help raise money for the famous children's hospital. Host a charity cake sale at home, work or in a community space to help fund life-saving research, fund new equipment and provide important support for families.
Bake it Better takes place from May 22-28. For more information, and to sign up and request a Bake it Better fundraising kit, visit www.bakeitbetter.org.
Find out how to host a charity baking sale
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