Preheat the oven to 190C/170C fan and lightly grease a 22cm diameter ring cake tin with butter.
Mix all the dry ingredients together in a large bowl. Pour over the melted butter and mix in the eggs. Spoon the batter into the pre-greased tin and smooth down.
Remove the stones from the cherries (or plums) – you can do this with a cherry stoner or by just pulling them apart and popping the stones out with your fingers. I like to do this over the cake tin, so that any juice drips on to the cake and adds colour. Drop the pitted cherries on to the batter and sprinkle the top of the cake with the remaining 20g of sugar and the roughly chopped pistachios. Bake for 50-60 minutes until the cake between the cherries goes all golden.
Allow the cake to cool in the tin, as it needs time to settle, then gently remove by running a knife around the edges. Covered well, it will keep in the fridge for up to a week (not much chance of that happening) but, for the best flavour, allow it to return to room temperature before eating.