Even those in the anti-white-chocolate party go for this: all the white chocolate does is cut through the necessary bitterness of the coffee (effortlessly supplied in the form of instant espresso powder) and together, with the cream, they make for an almost butterscotch-cappuccino taste. The best way to cook this sauce is the night before you want to serve it, so there’s plenty of time for it to chill down and firm up in the fridge. To be honest, 4–6 hours ahead is probably fine, but I sometimes find evening tinkering about in the kitchen easier than early-morning action. Once it’s whisked, poured into a jug and left to cool in the fridge, the sauce thickens voluptuously. If you don’t make this ahead, but use it from the pan, it’s rather like pouring a fabulous latte over your ice cream. Frankly, there’s nothing to complain about with either option: in both cases, we’re talking about a rewarding finale to a dinner menu that allows you to invite a whole gaggle of friends over without ending up resenting them for accepting.