This is a delicious way to have a nice soup to serve as an appetizer or with a sandwich or salad. When I can get celery on sale, as I did this week when it was half the usual price, I like to can this soup base. It is naturally gluten-free, which means that celiacs like Myrna can eat it too. Note that the soup is not canned in a pureed form; it is pureed right before serving, for safety.
Celery Soup Base
3 cups Celery -- diced; 1 large bunch, about 1 pound
1 cup Onion -- (about 1 medium)
1 garlic clove -- minced
1 tablespoon olive oil
2 Cups Potato -- peeled, diced (about 1 pound)
¼ Cup Sherry -- or white wine
1 quart Chicken Stock -- I used home-canned (or vegetable stock)
2 Tablespoons Heavy Cream per jar
Wash and trim celery, dicing into small pieces. Remove skin from onions and dice into small pieces as well as mincing the garlic clove. Sauté the celery, garlic and onion with the olive oil in a pot gently, to allow the vegetables to release their juices to prevent sticking, simmering for about 10 minutes (or until the onion is translucent). While the vegetables simmer, peel and finely dice the potato. Add the sherry or wine to the pot and stir to combine. Then add the diced potato and the stock, seasoning with salt and pepper and simmering for 5 minutes further. Set aside.
Position a funnel over the jar, using a slotted spoon divide the hot vegetables amongst approximately four pint jars per batch fill the hot jars to about 3/4 full with the vegetables then ladle the hot stock into the jars to a 1 inch (2.5cm) headspace. Remove any bubbles, adding extra stock if required to correct headspace. Wipe the rims of the jars with a clean, damp cloth (damped with vinegar) then wipe dry with a clean dry cloth or paper towel. Adjust seals and rings.
Place filled jars into preheated pressure canner (see your canner directions for the amount of water needed for your canner). Add canner lid and place onto high heat, once white steam is visible allow to vent for 10 minutes then add weight and begin processing at 10 pounds pressure (weighted gauge) or 11 pounds pressure (dial gauge) for 40 minutes (pints). Once complete, turn off the heat and allow pressure to return to zero before removing pressure canner lid (It takes my canner 25-30 minutes to return to zero). Remove jars after 5 more minutes to a towel covered tray to rest overnight. When jars are cold and well-sealed, remove rings and wash and label jars before storing.
To Serve: Heat the celery soup over medium heat until bubbling, then puree with an immersion blender carefully. Stir in two tablespoons of cream, simmer a little longer, pour into soup cups and garnish.
An alternate method is to blend the unheated soup in your blender, then pour into a pan and heat, adding the cream. Each pint makes about 2 cups of soup.
Yield: "4 pints"
I adapted this from the recipe on http://canninggranny.blogspot.com/2015/10/soup-of-day-celery-soup-base.html