Put the cauliflower florets in a saucepan, and fill with enough water to just cover the cauliflower. Boil the cauliflower for about 20 minutes until soft.
Meanwhile, heat the butter in a stock pot over medium heat. Cook the garlic and onions until soft and fragrant.
Add the flour to the garlic/onion/butter mixture and cook for one minute, until soft.
Gradually add the skim milk, whisking as you go to avoid lumps.
Add the softened, cooked cauliflower.
Blend it all up with your immersion blender, or transfer to a blender/food processor and blend until smooth.
Remove from heat, stir in the fat free half and half & lemon juice.
Sprinkle some parsley or chives on top