Rinse the zucchini and blanch with the beans in boiling salt water for about 5 minutes.
Drain, rinse in cold water and let cool. Rinse the spinach and blanch in boiling salt water. Drain the spinach, rinse and drain well. Squeeze well.
Chop the zucchini, beans and spinach. Mix with the herbs.
Toast the bread, cut into cubes and place in a bowl. Crumble the feta and mix with the grated cheese and bread.
Beat the eggs and season with salt and pepper. Pour the eggs into the bread mixture. Stir in the vegetables. Grease a large baking dish with olive oil and spread the vegetable mixture in the dish. Bake for about 35 minutes at 200°C (approximately 400°F), until golden. Remove from the oven, let cool and serve sprinkled with sesame seeds.