Put the sliced zucchinis in a bowl, add water and salt, and leave to soak for 20 minutes, then drain and pat dry gently, taking care not to break. Reserve.
In a medium skillet, add the olive oil and and add the zucchinis, stir for apron 5 minutes.
Remove the zucchini from the skillet, add the onions, sauté for about 5 minutes, add the sliced garlic, sauté for 40 seconds, add the red bell pepper, the fresh rosemary, salt and pepper and stir for 5 minutes more.
Add the vinegar and the olive oil stir for 2 minutes, turn off the heat and transfer the marinated zucchini into a clean and sterilized jar.
Replace the fresh herbs with 1 tablespoon of Herbes de Provence.
If you prefer, finish the antipasto with fresh mint leaves, finely chopped.
Put the antipasto in the fridge covered with plastic wrap and serve from the next day (for more flavor).
Serve the marinated zucchini with toast made from thinly sliced Italian bread, or along with your protein of choice or even as a pasta sauce!
The shelf life in the refrigerator will be up to 15 days.