Peel and finely chop the onion and garlic. Wash, quarter and slice the zucchini. Cut thin strips of lemon peel. Then squeeze the lemon half into a bowl.
Melt the butter in a saucepan and sweat the garlic and onion cubes with most of the lemon peel. Add the risotto rice for a short time and deglaze everything with the white wine and a tablespoon of lemon juice. Add the zucchini.
Cook the risotto over medium heat, stirring constantly, adding the vegetable stock over and over again until the grains are firm to the bite.
Finely chop as much basil as you like and mix with the Parmesan cheese into the risotto. Salt and pepper the dish. If you want, you can add more lemon juice, but that`s a matter of taste.
Put the risotto on a plate and garnish with the remaining lemon zest.