1. Chop the garlic and cut the parsley finely. In a bowl, mix the beef, the parmesan, the egg, the garlic, the parsley and the ricotta. Salt and pepper. Make into balls, and place them in the steam basket.
2. Wash the courgettes and peel the carrots. With the help of a Pyrex® peeler for thin skins, cut the tagliatelli out of the courgettes and carrots lengthwise. Cut the leeks into long slices.
3. Put the vegetable tagliatelli into the casserole dish with the water and the cooking salt.
4. Place the steam basket on the casserole dish and cover. Cook for 15 minutes from boiling point.