Clean, wash and slice the zucchini. Wash, quarter and seed the tomatoes. Finely dice the flesh. Peel garlic and press through a garlic press. Wash the thyme, remove the leaves, except some for garnishing, from the stalks and chop.
Cook the pasta in boiling salted water for about 8 minutes. Heat the oil. Fry garlic and zucchini in it. Deglaze with stock and cream. Add tomatoes and thyme. Season with salt and pepper. Cook for about 2 minutes.
Stir in the mustard. Add the sauce thickener while stirring, bring to the boil again and season to taste. Grate cheddar. Serve pasta and vegetable sauce sprinkled with grated cheese and garnished with remaining thyme.