Swiss Roll with Meringue Butter Cream

Beat the eggs and sugar until fluffy. Add the vanilla extract. Mix together the flour and baking powder and fold into the mixture along with the water.
Divide the mixture between two sheets of baking parchment, and spread out thinly. Bake in the centre of the oven at 250°C for about 5 minutes. Turn out onto a sheet of greaseproof paper sprinkled with sugar.

Meringue butter cream (Enough for 2 Swiss rolls)
Whisk the egg whites and sugar in a mixing bowl over a water bath until the sugar has dissolved. Remove the bowl from the heat and tip the egg whites into a mixing bowl. Whisk the meringue at high speed for 5-10 min. Reduce the speed to low/moderate and add the softened butter a little bit at a time. Make sure the butter is completely mixed in before adding the next piece, and whisk until the meringue is smooth. Purè e half of the berries using a liquidizer or hand blender. Press through a fine-mesh sieve if you want to remove the pips. Fold the purè e into the butter cream and stir carefully until smooth. The end result should be a fluffy and smooth cream. Tip If the cream curdles, it is easy to correct. If it is too cold, heat gently over a water bath for a short while and whisk back together. If it is too warm, leave to stand in the refrigerator for a while before whisking again.