Zucchini soup

• 3 tablespoons butter

• 1 large onion, sliced

• 1/3 pound (175 grams) broccoli

• 1 lbs (450 grams) zucchini / squash

• 4 cups (1 liter) of chicken stock (vegetarian option: can be substituted with vegetable stock)

• 2 eggs, lightly beaten

• 3 tablespoons parsley, chopped

• 3 tablespoons parmesan cheese, grated

• Salt and pepper

• Olive oil