Beat the egg whites until stiff, then trickle in the sugar, still beating, and continue beating until the mixture is shiny, white and firm.
Preheat the oven to 150°C with fan. Line baking trays with baking parchment.
Now fold the raisins, walnuts and ground almonds into the beaten egg white. Using two teaspoons place heaps of the mixture on the baking trays (leaving plenty of space between them!).
Put the macarons into the oven and bake for about 25 minutes. Cool on a cake rack and store in a well-sealed container.