In a saucepan over medium heat, combine the sugar, water and raspberries. Cook, stirring carefully so as not to damage the berries until the mixture is hot and the sugar is dissolved. Set aside to cool slightly.
Cut the crusts from the bread and cut the slices into strips. Fit the bread into a 1 litre pudding bowl to line the bottom and sides, reserving enough bread to cover the top. Fill in any gaps with small bits of bread. Add the raspberry filling then cover the top with bread.
Once the top is covered with bread, cover the bowl loosely with cling wrap. Place a weight on top of the bowl (like a heavy tin of something) and put in the fridge overnight.
When ready to serve, remove cling wrap and invert onto a plate. Serve chilled with whipped cream on the side.