Over a year ago, when I shared a recipe for caramelized onion quiche, I lamented the recipe writers who pretend that you can get truly caramelized onions in 10-15 minutes. Well, turns out I'm not the only one: Slate wrote an article earlier this month about that exact thing. Because the truth is, after 10-15 minutes, your onions will be white. Maybe a few brown spots. Maybe starting to become translucent. But definitely not caramelized.
Well the same holds true for French onion soup. It takes time. It's not hard, but it also won't be on the table in 20 minutes. Because those onions need time to become dark and soft and sweet and perfectly delicious. Give them at least an hour, if not more. Your taste buds will thank you.
Here's another point of note: Traditionalists will make onion soup with beef broth, for a true, dark flavor. Of course, those who keep kosher and want to top their soup with some ooey gooey cheese will steer clear of that, and I've found this soup very satisfying with vegetable broth.
French onion soup – serves 6-8
2 tablespoons oil plus 2 tablespoons butter or margarine
3 pounds onions, thinly sliced [maybe 10-15 onions, but really, weigh them]
3 tablespoons flour
8 cups vegetable or beef broth
1 tablespoon light brown sugar
salt and pepper to taste
Optional: cheese and croutons
In a large pot, melt the oil and butter together over low heat. Add the onions, toss to coat, cover and let sit on low for about 10 minutes to let the onions "sweat." Uncover, turn the heat up to medium (not high), and continue letting the onions cook, stirring regularly, for about an hour, until dark brown.
Add in the flour and stir until combined, then add in the broth, sugar, salt and pepper. Bring to a boil and simmer for another 10 minutes, then skim any fat off the top if desired. Season with salt and pepper to taste.
Serve with croutons and melted cheese if desired.