1. In a saucepan, boil the celeriac, cabbage and onion coarsely chopped.
2. When cooked, drain the vegetables, put them in a container and blend with a hand blender. Add the broth until you will have obtained a uniform and homogeneous cream.
3. Add to taste a spoonful of cream to make the soup even creamier.
4. Finish the dish with nutritional yeast and a slight sprinkling of pepper.