To make the base, crush biscuits into a fine crumb.
Next, melt the butter in saucepan over a low heat.
When the butter is melted, take it off heat and stir in brown sugar and biscuit crumbs.
Press the mixture into an 8-inch loose bottomed cake tin and then chill in the fridge for about an hour.
To make the topping, beat together the mascapone cheese, caster sugar, lemon zest and lemon juice until smooth and creamy.
Spread the topping over the base and chill for a couple of hours.
Remove from the tin and serve with a fruit coolie to cut though the sweetness of the cheese cake.