1. Rinse the broccoli under cold running water then divide it into small florets.

2. In a large pot combine the broccoli and enough water to cover it - roughly 1 liter (4 cups) should do the trick. Add 1 bouillon cube and bring the mixture to a boil at 100°C (212°F).

3. Reduce the heat to medium-low, around 80°C (176°F), cover the pot, and let it simmer for about 15 minutes, or until the broccoli is tender when pierced with a fork.

4. Drain the cooking water into a separate container and set it aside - you may need some of it later to thin out the soup.

5. Transfer the cooked broccoli to a blender or food processor and puree until smooth.

6. Return the broccoli puree to the pot and add 120 grams (4.3 oz) of crumbled feta cheese. Stir the mixture over low heat until the cheese is fully melted and the soup is heated through.

7. Season the soup with salt and pepper to taste. If it's too thick add some of the reserved cooking water a little at a time until you reach your desired consistency.

8. Serve the soup hot, topped with cooked shrimp and a sprinkle of chopped red onion if you like. A sprig of fresh parsley adds a nice pop of color to finish the dish.