I desperately want to try out the Salted Chocolate Tart from Simply Nigella but I am not a coffee fan. Is there anything else I can use as a replacement for the espresso powder or will the tart still work if I leave it out?
Nigella's Salted Chocolate Tart (from Simply Nigella and on the Nigella website) uses espresso coffee as the coffee helps to deepen the chocolate flavour. So you do not particularly taste the coffee in the tart filling and even those who dislike coffee amy still like the tart filling. If you don't regualrly have instant coffee or espresso powder at home but could buy a coffee from a coffee shop then you could replace 2 tablespoons (30ml) of the milk with the same volume of cooled espresso coffee.
Otherwise you could leave the coffee out completely but you may want to consider increasing the vanilla paste or extract from 1 teaspoon to 2 teaspoons.