Boil the cauliflower until completely tender then blend it. Prepare a béchamel sauce from the flour, butter and milk. Add to the blended cauliflower, dilute with the cauliflower broth and boil for another 15 minutes. After the soup is cooked, strain it through a colander.
Prepare a roux from the eggs and milk. Additionally, you can add a little butter. Optionally, you can braise the cauliflower pieces, roll them in breadcrumbs or bits of toast and put them into the soup.