For the cream of zucchini soup, dice the onion and sauté in olive oil until translucent.
Slice the zucchini, add to the diced onion and sweat. Add the vegetable boullion and bring to the boil. When the zucchini is cooked, puree everything with a blender.
Stir in double cream and some lemon juice, if desired. Refine with salt, pepper and finely chopped dill.