This is the BEST soup I've ever eaten, bar none! You could also make it substituting broccoli or brussels sprouts for the cauliflower. Even ppl who do not like cauliflower tell me they LOVE this soup ....
1NOTE: It helps to have everything pre-measured and lined up before you start, so you're not running all over the kitchen cutting and measuring, instead of paying attention to the stove. LOL!
2In large non-stick saucepan, melt butter over medium-low heat.
3Add onion and cook until golden, about 10 minutes, stirring occasionally. Don't let it burn!
4Stir in flour and salt; cook 2 minutes, stirring constantly. This is your roux; don't let it stick or burn!
5Gradually stir in chicken broth, stirring constantly to avoid lumps. When smooth, slowly add the 1-1/2 cups of water, continuing to stir.
Add cauliflower pieces and heat to a very light simmer. Cover and turn heat to LOW, to a bare simmer, until cauliflower is very tender, at least 20 minutes. Stir FREQUENTLY.
When cauliflower is very tender and mushy, add the milk and stir it in well. Bring entire mixture back up to temperature, but do not boil or allow milk to scorch.
6In a blender [with inner lid of cover removed to allow steam to escape], blend cauliflower mixture at low speed in small batches, until very smooth.
NOTE: You might prefer to leave some of the cauliflower florettes in there, instead of pureeing all of them. I save some aside, and just give them one quick mash w/ a hand masher. That leaves a little bit of 'texture' to the soup. But it is excellent in its pureed form, too.
7Return the entire mixture to saucepan; bring back up to temperature, until hot, stirring frequently. Don't let it boil.
8Remove saucepan from heat. Stir in dijon and 1-1/2 cups of the cheese until melted and smooth.
9Serving Ideas: Garnish soup with remaining cheese and serve right away with a hearty salad.
Serve with a warm, thick, chewy baguette. Great for a bread dipper!