1 Wash the sardines and divide into two fillets. Trim and wash the fennel and cut into eighths lengthwise. Then slice very thinly, lengthwise, using a mandolin if available. Reserve the fennel leaves.
2 Blanch the fennel in boiling, salted water for 1 minute, refresh in cold water and drain, retaining the cooking water. Take 250 ml of the cooking water and soak the raisins in it.
3 Finely chop the fennel leaves. Mash the anchovy fillets, peel and press the garlic. Finely crush the fennel seeds in a mortar. Mix the anchovies, garlic, fennel leaves and dill with the lemon rind and 3 tbsp olive oil. Season with salt and pepper.
4 Peel the onion and chop very finely. Boil a large pan of water for the pasta, add plenty of salt and cook the pasta until al dente.
5 At the same time heat the remaining oil in a frying pan and sweat the onion until translucent. Add the sardines and sauté over a medium heat. Add the fennel, the raisins with the soaking liquid, anchovy paste and pine nuts.
6 Dissolve the saffron in a little water and mix in. Season with salt and pepper and cook gently for 4-5 minutes. Drain the pasta, mix with the sauce and serve immediately.