Wisconsin Cauliflower Cheese Soup

This fabulous recipe comes from my younger sister, Brittany, who learned to make it because her girls love the Zuppa's version so much. It cured my craving for Zuppa's too, and I love that my family was eating an entire head of cauliflower and didn't even know it! Thanks Brittany!

2 Tbsp butter
1 medium onion, chopped
1/4 cup all-purpose flour
1/2 tsp salt
2 cups milk
1 (14 ounce) can chicken broth
1 head cauliflower, cut into 1-inch chunks
1 tsp Dijon mustard
1 (8 ounce) package sharp cheddar cheese, shredded about 2 cups
1 garlic clove, minced
1 1/2 cups water

In 4-quart saucepan, melt butter over medium heat. Add onion and cook until golden, about 10 minutes, stirring occasionally. Stir in flour, salt and garlic; cook 2 minutes, stirring frequently.

Stir in milk, chicken broth, and 1 1/2 cups water; add cauliflower and heat to boiling over high heat. Reduce heat to low; cover and simmer until cauliflower is tender, about 10 minutes.

In blender or with immersion blender blend cauliflower mixture at low speed until very smooth.

Return cauliflower mixture to saucepan. Remove saucepan from heat; stir in mustard and 1 1/2 cups cheese until melted and smooth. Garnish soup with remaining cheese to serve.