Peel and chop the onions and garlic. Fry half of each in 1 tablespoon of hot oil. Deglaze with 1/8 l broth, bring to the boil. Stir in couscous and let it swell covered for about 5 minutes. Wash and dice the tomatoes and add after about 2 minutes. Grate cheese, stir in half
Clean, wash and halve the zucchini. Hollow out halves, season. Finely chop the flesh. Fry with the rest of the onions in 1 tablespoon of hot oil. Deglaze with 1/4 l broth, bring to the boil. Season to taste. Pour into a large greased casserole dish
Place the zucchini in the mould and fill with couscous. Sprinkle the rest of the cheese on top. Cook in the preheated oven (electric cooker: 200 °C/ convection oven: 175 °C/gas: level 3) for approx. 30 minutes
Wash the basil and cut into strips. Mix with yoghurt, rest of garlic and 1 tbsp. oil, season. Arrange with the zucchini