Pasta con le Sarde

• 1/2 kg (1 lb 2 oz) fennel bulbs (if in Sicily use the mountain kind, called finocchielli)

Clean the fennel bulbs, trimming off bits which are too tough. Boil them for 10 minutes in water. Take them out, drain them, and cut them into very small pieces. Save the cooking liquid. Soak the sultanas for 15 minutes in warm water. Drain them. Remove the heads and backbones from the sardines. Take one third of them and cut them up very small to go in the sauce. The remaining two thirds are t