Cut the onion into fine cubes. Cut the zucchini lengthways into eighths and also cut into fine pieces. Either quarter the garlic or press it for a more intense taste.
Lightly sweat the onions and quartered garlic in a pan with olive oil and add the zucchini (add the pressed garlic only now). Season well with pepper.
Let sizzle for 1 - 2 minutes over medium heat and deglaze with half a glass (approx. 80 - 100 ml) of stock. Add the chopped parsley (frozen parsley is also possible) and simmer a little on a low level until the zucchini is cooked as desired. At the end add the cream cheese and season with salt and pepper if necessary.
If you serve the zucchini as a side dish, it can stay that way. If you want to make a sauce, you can dilute it by adding a little milk or broth.
It is best to mix the sauce with freshly cooked pasta and serve with grated Parmesan.