1. Melt butter in large stock pot. Add chopped onion and garlic and salt. Sauté for approximately 10 minutes over medium heat until onion gets golden translucent in color. 2. Add flour and stir to make a roux. Heat while stirring for a couple of minutes. 3. Slowly add Half and Half along with milk, stir entire time. Following the milk, gradually add water and chicken broth stirring constantly. 4. Add chopped cauliflower and heat until boiling. Reduce heat and simmer, covered, until cauliflower is tender (approx. 15 minutes). 5. Place contents of pan into blender and blend until smooth. Remove center part of blender cover to allow steam to escape. 6. Return cauliflower mixture to pot; add cheese and heat over medium heat until hot enough to melt cheese. Add mustard and stir until smooth. 7. Serve soup topped with a little cheese for garnish.