Cut bread into thin slices, place on a baking tray and bake in a preheated oven (electric range: 175 °C/ convection oven: 150 °C/ gas: level 2) for 10-15 minutes until brown, turning 1-2 times.
In the meantime clean and wash the zucchini and slice them into thin slices. Wash and clean the tomatoes and cut them into thin slices. Clean and wash the salad and pluck into bite-sized pieces. Mix lettuce, tomatoes, zucchini and olives carefully in a bowl.
Remove the slices of bread and let them cool down briefly. Season vinegar with salt, pepper and sugar. Fold in the oil. Wash the basil and dab dry. Pluck the leaves from the stalks. Chop half of the leaves and fold into the vinaigrette.
Add the remaining leaves with slices of bread to the salad and mix. Arrange salad and drizzle with vinaigrette.