In a medium bowl, combine raspberries with 75g caster sugar. Crush a few of the berries; set aside.
In a small bowl, dissolve 200g caster sugar in 80ml hot water. When dissolved, stir in Grand Marnier® and cold water; set aside.
Beat egg yolks with 75g caster sugar until ribbons form, about 5 minutes. Stir in mascarpone until smooth.
In a large glass or metal mixing bowl, with clean beaters, beat egg whites until foamy. Gradually add 75g caster sugar, continuing to beat until stiff peaks form. Fold 1/3 of the egg white mixture into the mascarpone mixture, then quickly fold in remaining whites.
Brush sponge fingers on both sides with Grand Marnier syrup. Place on bottom and sides of a 9x17.5cm glass dish. Spoon raspberries evenly over the layer of sponge fingers. Spread 1/2 of the mascarpone mixture over the raspberries. Sprinkle chocolate shavings over the top, then cover with the remaining mascarpone mixture. Top with toasted almonds. Cover with clingfilm, and chill in the fridge.