Dice the fennel bulbs and sauté them in a little fat. Pour in the water and the stock and cook for approx. 15 minutes until soft. Then puree everything very finely with the blender. Now stir in the lobster paste and season with the spices.
I like to tie the soup with a cube of light Dutch-style sauce.
Cut the fish into cubes and let it steep in the soup for 5 minutes at the end, under no circumstances let it boil at all.
If you like, you can add 100 grams of crab meat. You do it according to your taste.