This American style whisked sponge cake is made with puréed strawberries and vegetable oil rather than butter so is light but still moist and moreish. It will look amazing as a centrepiece next time you’re hosting guests!

Serves: 10
Preparation time: 1hr
Cooking time: 25-30min
Chilling time: 4hr

1. Preheat the oven to 180°C, Fan Oven 160°C, Gas Mark 4. To make the cake, grease and line the bases of 2 x 20 cm (8 inch) springform tins with circles of non-stick baking paper. Purée the strawberries then press through a sieve and discard their seeds. Mix the flour and baking powder together in a second bowl.
2. Add the egg yolks, oil, lemon rind and 175g of the sugar to the bowl of an electric mixer. Add the strawberry purée and a little food colouring and whisk for about 5min until very thick.
3. Wash and dry the whisk then beat the egg whites until stiff moist looking peaks then gradually whisk in the remaining 50g sugar a teaspoonful at a time until the mixture is smooth and glossy.
4. Sift the flour and baking powder over the top of the strawberry mix then gently mix in. Stir in a large spoonful of the egg whites to loosen the mixture then add the rest and very gently fold in so that you keep as much air in the mixture as possible.
5. Spoon the mixture evenly between the two tins, gently ease the tops level then bake for 20-25min until the top is set, very lightly browned and a skewer comes out cleanly when inserted into the centre of each cake. Leave to cool in the tin for 10min, then remove the sides and leave to cool. Remove the base when cold. (The cake will sink slightly as it cools.)
6. When the cakes are cold, peel off the base paper. Cut each cake in half horizontally, then put two of the halves to one side. Keep the other two halves, still stacked then cut out a circle from the centre using a smaller 15cm baking tin as a template. (This centre circle can be given to the kids or eaten now with a cup of tea!)
7. Put one of the whole circles of cake on a serving plate, spread a band of jam around the outer edge about 2.5cm wide then place one of the ring cakes on top. Spread the top edge with jam, then add the second cake ring.
8. Add the cold water to a small heatproof bowl, sprinkle over the gelatine, making sure that all the dry powder is absorbed by the water. Set aside for 5min.
9. Pick out the best strawberries and arrange over the inside of the cake, when you know you have enough, take them out and reserve on a plate. Purée 175g of the remaining strawberries then press through a sieve and discard the seeds.
10. Stand the bowl of gelatine in a saucepan of gently simmering water and cook for about 5min, stirring from time to time until it becomes a clear liquid. Whisk the cream in a bowl until it forms soft peaks, add the strawberry purée and gradually mix in the gelatine until smooth. Spread a few spoonfuls in the base of the centre of the cake, arrange the whole strawberries on top then cover with the remaining strawberry cream. Stick the remaining cake half in place with jam around the edges as before. Chill for 4hr.
11. About an hour or so before serving, whisk the mascarpone, lemon rind and icing sugar together in a bowl then gradually whisk in the cream until soft and spreadable, don’t be tempted to whisk too vigorously or the frosting will be too thick to spread. Take out one third of the frosting and divide between two small bowls, colour one pale pink, the other a deeper pink.
12. Spread a very thin layer of the uncoloured frosting all over the cake to stick the crumbs in place then spread a thicker layer all over, being more generous on the top. Spread the sides smooth with a knife. Using a teaspoon and round bladed knife, press small dots of dark pink frosting in a band around the base of the cake. Make a second paler pink band above it and a third plain band of uncoloured frosting then smooth the sides to merge the colours with a palette knife. Decorate the top of the cake with edible flowers and small strawberries, if liked.

Cook’s tip: As this cake is quite involved, you might prefer to make the cake the day before then wrap in foil or make and fill the cake then chill overnight and just decorate with the frosting an hour or so before you want to serve it and keep it in the fridge.