- With the rack in the middle position, preheat the oven to 200 °C (400 °F).
- In a skillet, soften onion in oil. Add veal and cook while crumbling until it begins to brown. Add crackers, wine and broth. Simmer while stirring until mixture has absorbed almost all liquid. Off the heat, add cheese. Season with salt and pepper. Set aside.
- On a large baking sheet, combine tomatoes, onion and olive oil. Set aside.
- With a small spoon, scrape inside zucchini halves to create a cavity along the entire length. Keep zucchini pulp for another use. Stuff each zucchini half with veal mixture. Place stuffed zucchini halves on the baking sheet with tomatoes and onions.
- Bake for 30 to 35 minutes or until zucchini are tender and tomatoes burst. Sprinkle with cheese before serving.