I make the original recipe (with a few modifications) up to the point where she adds the cream, and then can it. After reheating, we add the cream.
Canned Cream of Tomato Soup Base
3 T. ghee, tallow or lard
1.5 c. chopped red onions
2 carrots, chopped (I use 1 c. juicer pulp)
1 T. minced garlic
4 pounds vine-ripened tomatoes, coarsely chopped*
3 c. stock (I use chicken or veal)
1 T. salt
3/4 c. cream
Heat fat in a large heavy bottom pan over med heat and saute onions and carrots until very tender. Add garlic and saute 1 minutes. Add tomatoes, paste, stock and salt. Bring to a boil, reduce heat, and simmer until tomatoes are very tender, 30-40 minutes.
Put through a food mill, discarding the dry pulp, OR blitz in a blender for 3 minutes until smooth.
At this point, you can either stir in the cream and serve it; or, pressure can it. You MUST use THIS GUIDE to determine the pressure/time for your area. Yes, the link is for canning meat, and that is the correct one to use because of the fat and onions in the recipe. Do NOT use the pressure/time for canning tomatoes, and DO NOT WATER BATH CAN!!!!! (Seriously, you can die if you do!)
I use pint jars, leaving 1.5" headroom, then process for 75 minutes. One pint jar is a meal for one person when served alone, or for 2 people when served with a sandwich. If you use quart jars, leave 2" headroom and they must be processed for at least 90 minutes.
*If you prefer a chunky soup, you can peel and seed the tomatoes before cooking them and then skip the food mill/blender.