Sweet-Sour Onion Soup

Regular readers know I love a good bowl of soup and often make gallons of soup at a time. In fact I make soup much more often than I post about it because 1. I forget to write down what I'm doing and/or 2. I'm doing it on the fly and not paying attention to exactly how much I've thrown into the pot when. I'm kind of a Soup Improviser.

But this latest improvisation in soup was so hauntingly delicious (and simple) I just have to share even if it is more of a technique than a recipe.

The story begins with my husband snagging a well-loved, used five-quart red enameled cast iron Le Creuset French (i.e. Dutch) oven at a local estate sale for just $18.

After I washed it, I had set it on my stove top to dry. I was looking at it and was suddenly overcome with the urge to make soup. Onion soup. One where you sweat the onions and slowly caramelize them into melt in your mouth sweetness, which a pot like this does better than any other. One inspiration led to another until before I knew it is was Sweet-Sour Onion Soup.

Here's how to do what I did:

Melt a knob of butter with a glug of olive oil
Slowly sweat/caramelize very thinly sliced yellow onions (I used 2 gigantic and 1 regular size onions) (use a low heat and a heavy pan)
Add dribbles of oil if onions seem dry as they slowly turn brown and soften. Continue to cook (uncovered), stirring occasionally until the onion's cell structure totally changes and the slices now are quite sweet and and the onions are falling apart soft and virtually melt in your mouth.
Add 1/4 cup sherry vinegar, salt, pepper, a bay leaf and about a half teaspoon of ground French Provencal seasoning and a pinch of red pepper flakes. Mix well and continue to cook for a few minutes.
Add 1 quart of good quality beef stock and 1/4 cup of dry sherry. Mix well, raise heat to medium, bring to a simmer and cover. Adjust heat and allow to simmer for about 10-15 minutes until soup is heated through. Taste and adjust seasonings. Add more vinegar if the taste isn't sour enough. Add more butter to tame a too tart taste. Simmer until the additions, if used, are absorbed. Remove bay leaf.

Serve hot with cheese-topped croutons. Try with bits of shaved cheddar or other cheese mixed into the hot soup in the bowl.

FYI -- This is my second Le Creuset. I gave myself a gift of a 7 1/2 quart oval French oven (in blue) a year or so ago. I go mine as a factory second at about half retail price at discount retailer that does not offer the same merchandise on line. I've been so enamored of its enameled goodness that I wanted a second, round one, but at even a better discount. Thanks to Mr. Blog Appetit who spotted the estate sale during his morning power walk.
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Photo credit: Le Creuset website