Boil 1/4 litre of water, 1 tablespoon of oil and 1 teaspoon of salt in a large pan. Remove the pan from the heat and stir in the couscous, let it swell for 2 minutes. Take out and let it cool down.
Peel the vegetable onion and cut into large pieces. Clean, wash and cut the bell peppers into pieces. Clean and wash the zucchini, cut them in half lengthwise and cut them into slices. Wash, clean and chop the tomatoes.
Heat 2 tablespoons of oil in a frying pan. Brown the vegetables except the tomatoes. Add the tomatoes and tomato paste, season with herbs from Provence, salt and pepper. Add 1/8 litre water, bring to the boil and simmer for about 5 minutes.
Grate cheese. Wash the thyme, pluck the leaves from the stalks. Mix cheese, thyme and couscous. Put the vegetable mixture into 4 small or 1 large casserole dish. Cover with couscous mixture.
Bake in the preheated oven (electric cooker: 200 °C/ convection oven: 175 °C/ gas: level 3) for about 15 minutes.