Heat the olive oil in a pan, add chopped onion, garlic and fry for 1-2 minutes. Add sliced cauliflower and saute it for about 5-7 minutes. Afterwards add milk, salt, pepper and cook on a low heat until cauliflower softens.
Meantime, heat broth in another pot, add sliced broccoli (small pieces),grated carrot and cook.
When cauliflower gets soft, mix it in a blender. Add in the cheddar cheese, cooked broccoli together with broth and cook until cheese melts. You can either blend the broccoli or leave it as it is in pieces.
When the soup is too thick, you can add a bit of more broth or milk. Season according to your taste.
You can serve it with whole-grain croutons. Enjoy 🙂