For the base:
- 100g shortbread biscuits, crushed
- 300g chocolate chip cookies, crushed (you can actually do 200g and 200g, see what you can buy)
- 80g melted butter, for the base
For the caramel layer:
- 150g butter
- 150g dark brown soft sugar
- 397g can Carnation Condensed Milk
For the chocolate top:
- 200g milk chocolate
- 50g white chocolate
Melt the 80g butter on a low heat. Crush the biscuits in a bag with a rolling pin - good if you are feeling aggressive! Put the biscuit in with the melted butter and stir until all the biscuit is coated and kind of sticking together.
Put the biscuit mix in a dish (brownie tin is ideal) lined with baking paper. Press down with the back of a spoon. Leave to cool in the fridge for about 20 minutes.
Meanwhile, melt the remaining butter (150g) and then add the sugar. Stir on a low heat until all has dissolved (it doesn't actually disappear so just stir until it looks like nothing else is going to happen).
Now pop the condensed milk in. Ramp up the temperature. Stir like mad. It will begin to thicken and the butter will be absorbed into it all. When it starts to boil, keep stirring until it is nice and thick - it should be almost like when you make a cake but before you have added the flour - gloopy (like custard). It takes longer than you think.
Take it off the heat. Go and get the biscuit base from the fridge. Pour the caramel onto the base (you don't need to let it cool as my Aunt, Ali, sagely asked when I was fortunate enough to stay whilst I was in London). Put it back in the fridge until it has set (about an hour and a half).
Melt the chocolate in different bowls over boiling water. Put the milk chocolate on first then put dollops of white chocolate all over and spread about with a knife/spoon/other utensil. #marbling
Leave to cool in fridge for a good couple of hours. Cut up. Eat. Enjoy. Boom!