Place anchovy fillets in milk. Peel, wash and slice the potatoes and cook them for 15 minutes in boiling salted water. Wash and slice the zucchini. Add to the potatoes after 10 minutes, then drain and keep warm.
Meanwhile wash the lamb, dab dry, press slightly flat, season with salt and pepper. Drain anchovy fillets and crush them with a fork. Heat the oil in a pan, fry the meat for about 4 minutes on each side, remove and keep warm.
Add the anchovies to the frying fat and sauté briefly. Finely chop rosemary needles, add and deglaze with cream, bring to the boil. Cut the meat open and serve with the vegetables and sauce. Sprinkle with coloured pepper.
Garnish with rosemary as desired.