Wash and clean the zucchini, but do not remove the stalk end. Cut the zucchini lengthwise three times almost to the end of the stem. Cut feta cheese into about 12 long strips. Cut tomato peppers into long pieces as well.
Place 1 strip of feta cheese and 1 pepper piece in a zucchini incision. Wash the rosemary, thyme and oregano, dab dry and chop, except for a little to garnish. Peel the garlic and press it through a garlic press.
Mix garlic, herbs, 5 tablespoons of olive oil and freshly ground pepper and brush the zucchini fans with it. Cover and leave to marinate for about 30 minutes. In the meantime, wash, quarter, seed and finely dice the tomatoes.
Onion peel and likewise chop finely. Chop the olives, except for a few for garnishing. Heat 2 tablespoons of olive oil in a pan and sauté the onion briefly. Add tomatoes, stock and vinegar, bring to the boil briefly.
Stir in olives and season with salt and pepper. Let it cool down. Place zucchini fans on a grill tray or aluminium foil, sprinkle with salt and grill on the preheated grill for approx. 20 minutes.
Serve with tomato and olive sauce.