Peel and finely chop the onions and sauté them in the butter in a large pot.
Wash the leeks and celery, chop finely and add them along with the peeled and diced potato and the sprig of thyme.
Sauté everything nicely for a few more minutes.
Deglaze with the chicken broth; if you prefer a thicker soup, start by adding 1.5 l. Once blended, you can add extra water as desired. You can also omit the potato if you're not a fan, as it mainly serves to thicken the soup.
Let everything simmer for 20 minutes until all the vegetables are soft, then blend everything finely for the first time.
Add the washed and drained chervil and blend everything again, taste and season with pepper and salt.
My grandma always added a splash of cream to take away the slight bitterness of the chervil, I still enjoy that just as much. 😊
For the Halloween touch:
Scoop a spoonful into a deep plate at the table, so you don't have to move the plate anymore, and place a few mozzarella balls in it.
Slice thin rounds of the washed carrot and place them on top, put a few fish roe on the carrot slice.
There you have the spooky eyeballs, I see what you don't see grrrrrr!