Dice the rolls, soak them briefly in the warm milk, wash the zucchini, cut in half lengthways. Remove the seeds with a teaspoon. Finely dice the sheep`s cheese, also finely chop the olives, finely dice the shallots and garlic.
Steam shallots in oil until translucent, deglaze with white wine, add to the minced meat with sheep`s cheese and olives. Squeeze out the rolls, mix with the meat with the garlic, eggs and thyme, season everything well with salt and pepper. Place the minced meat in the zucchini halves and sprinkle with parmesan. Place the vegetable boats in a large casserole dish and cook in the oven on the middle rack for about 20-30 minutes, possibly turn on the grill to finish the gratin (but be careful! The parmesan burns easily).
Mix the crème fraîche, lemon juice, a little salt and pepper to a sauce and serve with the zucchini.