1/4 cup butter
2-3 celery stalks
1 onion
1 quart chicken stock
16 oz frozen cauliflower
salt
Melt the butter in a large saucepan over low heat as you coarsely chop the celery and onions. Turn up the heat to medium-high and saute the chopped celery and onions until softened, about five minutes. Add the broth and bring to a strong simmer, about five minutes. Add the cauliflower and about a teaspoon of salt, and bring back to a strong simmer. Simmer until the cauliflower is tender, about ten minutes.
Puree the soup with whatever you have, like a food processor or a blender will work. What I have is the Cuisinart SmartStick Hand Blender, which is awesome and as easy to wash as a spoon.
I divide up the soup between 4-5 jars for the week's lunches.
To serve, I pour the jar into a bowl, top with pan-roasted chicken breast, and reheat in the microwave.