Classic soup perfect for colder weather ahead

Fall weather calls for warming soup and crusty bread. What better choice than a classic filled with sweet yellow onions?

During a recent trip to Paris, I found some version of cheese-topped onion soup (soupe à l'oignon gratinée) at practically every bistro at any hour (including well past midnight). Did they keep a big pot simmering all day and night?

No, they had shortcuts for this not-so-fast comfort food. The onions were caramelized ahead, slow-cooked in butter either on top of the stove or in the oven. The broth (usually beef) was cooked ahead, too. The two were combined and warmed gently.

A crusty crouton, made from stale bread or baguette, was positioned at the bottom of an ovenproof bowl. The onion-broth mixture poured over the crouton, the soup-soaked bread forming a platform for a mound of cheese on top so it didn’t sink to the bottom. The whole thing was popped under the broiler until the cheese bubbled. Voilà!

Now, to try this method at home, I discovered – like a lot of French food – it wasn’t as simple as it looks.

That starts with the onions. Most recipes call for the onions to be totally caramelized, meltingly soft and rich brown in color. That takes time – 45 to 60 minutes on top of the stove, 3 hours in the oven, while stirring often. If they get too brown, the onions become bitter. To retain their sweetness, sauté until golden, not dark. (That takes a lot less time, too.)

I wanted the broth to taste more like onion than something else, which meant the broth needed to be thinned. (Using only broth, as recommended in some recipes, the soup became too salty as it cooked down.) In my version, the onions finish cooking while simmering in the broth, melding the flavors.

For the crouton to stand up to the soup, it needs to be really, really hard and dry. Otherwise, it just dissolves when the soup is added.

The crouton also needs to be thick enough that it can act as a base for the cheese. (Some recipes suggest stacking two croutons.) Otherwise, the cheese sinks and disappears into the broth.

As for the cheese, it melts on top of the soup without broiler time. The broiler gives the cheese a nice sizzle and forms a crust, but it’s not really necessary (especially if your bowls aren’t ovenproof).

Serve with crusty bread (preferably not day-old). Bon appétit!

French onion soup

Makes 4 bowls

Ingredients:

4 tablespoons butter

6 cups yellow onions, thinly sliced

4 cups broth (beef, chicken or vegetable)

2 cups water

1 tablespoon fresh thyme or 1 teaspoon dried thyme

1 tablespoon fresh parsley, chopped, or 1 teaspoon dried parsley

½ teaspoon red pepper flakes

2 tablespoons brandy

4 slices day-old French bread or 8 slices day-old baguette

Butter

1-1/2 cups Gruyere or similar cheese, shredded

½ cup Parmesan cheese, shredded

Instructions:

In a large and heavy pot, melt butter over medium heat. Add onions. Sauté onions, slowly, stirring often, until they become very soft and start to turn golden brown, at least 20 minutes.

Add broth, water, thyme, parsley, red pepper flakes and brandy. Bring soup to low boil, then reduce heat. Simmer 20 to 30 minutes.

Meanwhile, make croutons. Preheat oven to 300 degrees F.

Butter a baking sheet. Place slices of bread or baguette on the prepared baking sheet and bake in the oven until nicely browned and very dry, turning slices after 10 minutes. This process takes about 20 minutes, depending on the dryness of the bread.

To serve, place toasted croutons on the bottom of each bowl. Ladle soup over croutons while filling bowls halfway. Wait a minute while the bread soaks up the soup, then add some more soup to the bowls.

Mix together the two cheeses. Generously pile the shredded cheese on top of each bowl, about ½ cup total per bowl. If desired (and the bowls are ovenproof), put the bowls on a rimmed baking sheet and return to the oven for 5 to 10 minutes, so the cheese melts and forms a crust over the top.

Serve hot with more French bread or baguettes.