My chocolate cheesecake mousse is very solid as a mousse (I call it 'mousse' as I serve it in glasses, with cream) and it can easily be set in a cake tin and served in slices like cake.
1 x 100g bar 85% dark chocolate
4dsp Splenda
1dsp vanilla extract or orange extract for a Terry's chocolate orange spin on it
1 egg
2 x 250g tubs cream cheese
1 small tub double cream
Melt the cream, chocolate, Splenda and extract in a bowl over simmering water.
Whisk in the egg using an electric whisk at high speed until mixture has cooled.
Bung in the cream cheese and whisk until thick. The more you whisk the thicker it gets. It's not that airy, but pretty solid.
Line a small loose-bottomed cake tin with clingfilm, spoon in the mixture and smooth/press it down with a spoon.
Refrigerate.
Turn out, slice with a hot knife, serve with cream. And perhaps some more cream*.
*if you like cream as much as I do.
Also makes nice truffles - just roll spoonfuls of it into balls.
Or for individual puddings, serve in a glass with a spoon.