Nothing says British summer like strawberries and cream. Think lazy afternoons watching tennis surrounded by hounds in your rotting ancestral country house.
In a saucepan, heat the strawberries, caster sugar and water together. Cook until the strawberries have broken up and the sugar has dissolved. Remove from the heat and stir through the liqueur.
Find an 8 by 12 inch baking dish. Dip the biscuits two at a time in the strawberry liquid, then arrange them to fill the bottom of the dish.
Meanwhile, prepare a hot water bath with a pan of hot water with a glass heatproof bowl over it. Add the eggs, sugar and salt and whisk. Use a digital thermometer to check the temperature of the eggs - keep whisking until it hits 71°C.
Remove them from the heat and use an electric whisk to whisk the eggs until the whisk leaves a trail behind it. At this point, beat in the mascarpone a large spoonful at a time.
Spread a third of the mixture over the soggy fingers, then top with halved strawberries. Repeat, until you have three layers of biscuits.
Pipe the remaining mixture on top and scatter with the strawberry powder.
Pop in the fridge for at least an hour.
