Put the olive oil in a pan. Sauté the garlic cloves and onions in it. Add the sliced mushrooms and zucchini one after the other and fry each for approx. 3 minutes. Season to taste with salt, thyme and oregano. Now add the parsley and vegetable stock and let simmer for about 10 minutes in a closed pan. Then add the peeled and sliced tomatoes and cook for another 2 minutes. Finally stir in the olives and crème fraiche. Finally, season again to taste.