Combine yoghurt and mascarpone.
Choose a deep serving dish, preferably about the same width as your sponge cake. Depending on your chosen bowl, split the cake into rounds. The usual double unfilled sponge will give you four discs if you cut each sponge side in half.
Brush both sides of the cake discs generously with the syrup, but not so much that it starts falling apart.
Layer the trifle, considering that you will have four sponge layers to cover. It's nicest to use up the cake. If you misjudge and only end up using three sponge layers don't stress & use the leftover sponge for morning tea.Start with yoghurt mix, then top with cake, then the strawberries. Drizzle all these with syrup.Continue layering, finishing with yoghurt mix on top. Decorate with additional fruit.
Refrigerate until serving. Any remaining syrup can be put on the table or used tomorrow to drizzle over ice cream.