Anyway, as with most of her recipes, Corbin allows for substitutions; in this case her variations might include young turnips, shallots, celery, rutabagas, beets, or peppers, as well as many herbs. But the ingredients listed below form her suggested, go-to soup base (and just in case you're wondering, it's filed under celery because we substitute celery root for actual celery). She also notes that you'll want to use veggies and herbs that have the strongest taste and scent you can find.
Souper Mix
Makes three to four 8 oz. jars
9 oz. leeks
7 oz. fennel
7 oz. carrot
9 oz. celery root (or celery)
2 oz. sun-dried tomatoes
2 or 3 garlic cloves
3.5 oz. parsley
3.5 oz. cilantro
3/4 c. plus 1T salt
Put all ingredients into a food processor and blend together. The result will be a moist, granular paste. Spoon into sterilized jars and seal with vinegar-proof lids. Keep one jar of the mix in the fridge for everyday use, while the rest can be stored in a cool, dark, and dry place. Use within 6 months.
To use the souper mix, just stir about 1 teaspoon of it into 1 cup of hot water.