Preheat the oven to 170c fan/190c/325f/gas mark 3.
Line a 1kg loaf tin with baking paper, I use inserts, they are much quicker.
In a food processor, whizz the biscuits and peanuts until they are crumbs, you can leave it a little rougher with some chunks remaining.
Melt the butter and stir it through the biscuit crumbs.
Pour into your loaf tin and press down firmly, then pop in the oven for 15 minutes. Leave to cool then pop in the fridge until you need it, or overnight.
Before you make your filling, you will need to heat the oven again to the same temperature you used for the base.
Whip together the mascarpone, sour cream and philadelphia with a wooden spoon, then add the sugar and eggs. Keep whipping until it is well combined and smooth.
Add the chunks of snickers and mix in.
Pour the mixture on top of the biscuit base and bake for an hour and a half. Turn the oven off, but leave the cake in. A fudgey topping with develop. Don't worry about how long it needs left in the oven, just take it out when you see the top has browned a little.
Leave the cake to cool in the tin, then lift it out carefully and pop it in the fridge until you are ready to serve it.
Before serving, drizzle the cake with toffee sauce and a scattering of peanuts.
