Cook the pasta in boiling salted water until just al dente. Set aside 100 ml of cooking water, drain the pasta.
Heat the oil in a frying pan, add the garlic, sauté briefly. Add the breadcrumbs, toast for approx. 3 mins., remove and set aside.
Heat the oil in the same frying pan, add the fennel, stir fry for approx. 10 mins. Add the lemon zest and juice, season, simmer for approx. 1 min. Add the pasta and reserved cooking water, mix and heat gently. Mix in the reserved breadcrumbs.