To make the base use a food processor to whizz up the biscuits into crumbs, or bash them gently with a rolling pin in a bowl or sandwich bag
Mix the melted butter into the biscuit crumbs, and press the mixture into the bottom of a 23cm springform tin until compact and even. Put it in the fridge while you make the filling
For the cheesecake filling use a food mixer with a whisk attachment or an electric hand whisk to mix together the cream cheese, icing sugar and salted caramel sauce
Once it is smooth with no lumps, add the double cream and whisk until it is very thick and holds it's shape. You want it to get to a stage where you can scoop some up with your spatula or spoon and you have to give it a tap on the side of the bowl or slight flick of the wrist to get the mixture off the spoon. If it’s sloppy and slides right off the spoon without any encouragement needed, then you need to mix it more
Smooth the mixture into the tin on top of the biscuit base, then put it in the fridge overnight, or for at least 4 hours, to set
Remove from the tin and put on your serving plate. Smooth the sides with a butter knife to create a neater finish
To decorate, put the salted caramel in a bowl and microwave it for 15-30 seconds so it is pourable. If your sauce is already runny you don't need to do this. Let it cool for a minute or so, so you're not pouring hot liquid onto the cheesecake
Pour the sauce over the cheesecake and let it spread and drip down the sides. Use a palette knife to smooth it out and push it to the edges if it doesn't spread/drip enough
Serve immediately, store any leftovers in the fridge and eat within 2-3 days