Peel the garlic and press it through a garlic press. Heat the oil in a pot. Sweat tomato paste and garlic for 2 minutes while stirring, dust with flour and mix. Deglaze with 600 ml vegetable stock.
Boil up while stirring. Season to taste with salt, pepper, sugar and thyme. Quarter the peppers, clean, wash and cut into strips. Peel onion, chop coarsely. Wash, clean and slice the tomatoes.
Wash and clean the zucchini and aubergine, cut them in half lengthwise and slice them. Grease casserole dish. Mix vegetables and fill into the dish, pour tomato sauce over it and sprinkle with cheese. Bake in the preheated oven (electric cooker: 200 °C/ convection oven: 175 °C/ gas: level 3) for about 30 minutes.
Ciabatta is delicious with it.