Break broccoli into florets, cut potatoes into cubes, cut onion into half-rings.

Fry onion in oil for 5 minutes, then add potatoes and fry for additional 10 minutes.

Pour vegetable stock, salt, pepper and bring to boil. Add broccoli, cook for 10 minutes.

Blend vegetables with stock until puree, mix with grated cheese and cook through.

When serving, top the soup with greens.