Heat oven to 180C/fan 160C/gas 4 and
make sure there’s a shelf ready in the middle.
Line a 12-hole bun tin with fairy cake cases.
Beat the butter, sugar, flour and eggs with
4 tsp of the coffee and a pinch of salt until
creamy. Stir in the chopped walnuts.
Spoon the mix into the cases (start by
adding 1 heaped tsp to each, then go back
and top them up – that way they should all
be of equal size), then bake for 18-20 mins
until light golden and springy. Cool for a few
mins in the tin, then lift the cakes out and
cool completely on a rack.
Put the mascarpone, 3 tsp more of the
coffee and the sugar into a large bowl, then
beat together. Spread a dollop of the coffee
cream onto the top of each cake, then finish
with a walnut half. The cakes are best if
they’re iced fairly near the time of eating,
so if you’re making ahead, whip up the
mascarpone mix, keep in the fridge, beat
it again, then spoon onto the cakes just
before serving. Un-iced cakes will keep up
to 2 days in an airtight container.