Few things are more promising than a piping-hot bowl of French onion soup placed before you on a brisk day, its fragrant liquid beneath a toasted raft topped with golden cheese that will soon be stringing from your mouth. How frustrating, then, to discover something skimpy, with bready mush and pale onions, devoid of flavor.

Having been subjected to three such disappointing examples at restaurants in the fall, I decided to work through what it takes to make a soul-satisfying version.

Onions became the focal point of my tinkering with other cold-weather classics, including croque monsieur, and a savory tart.

The soup has three make-or-break components: broth, onions, cheese. An excellent rendition is layered with flavor and nuance. It starts with an excellent stock; without it, your soup will be average, at best.

Essentially, it’s best to make a stock from your stock; that is, bump it up by simmering it for 35 to 45 minutes with several skin-on onions (to deepen the stock’s color), celery with leaves (packed with flavor), thyme, black peppercorns and bay leaves. Don’t use carrots; caramelized onions will provide the final product with enough sweetness.

Any hearty meat stock (chicken, duck, beef) works in this soup as a fine foil for the onions. By the way, I’m not against using some bouillon cubes or onion powder or salt to add flavor, or even Kitchen Bouquet to deepen the color of a broth that looks wishy-washy.

Experimenting with yellow, white and Vidalia onions, I discovered that, yes, the Vidalias were sweetest; in fact, too much so to use on their own. I discerned little difference between the yellow and white onions. The soup versions with all yellow onions and half yellow/half Vidalia both had a fine balance of sweet to savory.

The goal in caramelizing onions is to get some color, and therefore flavor, on them quickly and cook them long enough to get rid of their water (10 cups of raw will reduce to barely two cups cooked) and deepen their flavor.

To that end, I place a large saute pan over medium-high heat. When it is very hot, I spread the onions in the pan and don’t touch them for several minutes so their moisture starts to evaporate. Then I add fat and still let them be for several minutes, until I notice that caramelization has begun. At that point, I season, stir, reduce the heat and cook for about 25 minutes, stirring and scraping up browned bits from the bottom every so often. Result: deeply browned strands of concentrated flavor and sweetness.

Into a pot they go with the stock for simmering and melding, fortified with bay leaves and finished with port wine (for its depth and caramel quality) and fresh chopped thyme. Adding those ingredients too soon diminishes their impact greatly.

Gruyere is the standard for onion soup because of its distinctive nutty notes. But I found that a mixture of cheeses provided more complexity and interest. After experimenting, I settled on semisoft fontal, a melty and much less expensive Italian cheese, which added the creamy note I sought.

Eyeing the caramelized onions sitting on the counter, I had a light-bulb moment. Using scraps left over from making two pies that day, I rolled out a third crust and blind-baked it in a 9-inch tart pan. I covered the baked shell with the onions, topped them with ham and Mornay sauce and broiled what became a gooey, onion-soup-meets-croque-monsieur tart. A small slice makes a perfect winter first course; a larger one with a simple green salad is entree-worthy.

French Onion Soup

1 baguette, cut into ½-inch slices

2 pounds (4 medium) yellow onions, peeled, halved from top to bottom and sliced into 1/4-inch half-moons

4 large fresh bay leaves

2 tablespoons canola oil

2 tablespoons unsalted butter, cut into cubes


Freshly ground black pepper

1/8 teaspoon onion powder

8 cups homemade veal, beef, chicken stock or smoked chicken stock (see headnote)

1/3 cup port (may substitute Madeira, sherry or dry vermouth)

1 teaspoon chopped fresh thyme leaves

2 cups grated Gruyere cheese

2 cups grated fontal cheese

Preheat the oven to 375 degrees. Spread the baguette slices in a single layer on a baking sheet and bake them for 15 to 20 minutes, until lightly browned and hard.

Heat a large saute pan over medium heat for several minutes. Spread the onions evenly in the pan, along with 2 of the bay leaves, and let them sit for a couple of minutes. Drizzle the oil evenly over them and dot with butter. Do not stir them for several minutes.

Stir the onions, scraping up the browned bits from the bottom of the pan. Season to taste with salt and pepper. Let the onions cook, stirring often, for 20 to 25 minutes, until golden brown and nicely caramelized.

Transfer the onions to a large pot and add the 2 remaining bay leaves, the onion powder and the stock. Season with ½ teaspoon salt and 1 teaspoon pepper. Bring to a boil over medium-high heat; reduce the heat to medium and cook, uncovered, for 15 minutes, at a very slow boil.

Position a rack in the upper third of the oven and preheat the broiler to high. Line a rimmed baking sheet with aluminum foil and place 8 onion soup crocks on it.

Stir the port and thyme into the hot soup, and ladle it into the crocks stopping a half-inch short of their rims. Discard bay leaves. Float 2 or 3 slices of baguette on top: You want to cover the surface of the soup without the bread overlapping. Combine the Gruyere and fontal cheese in a small bowl. Sprinkle ½ cup of the cheese mixture evenly over the toasts in each crock (don’t skimp!) and broil for 3 or 4 minutes, until the cheese is bubbling and well browned. Serve immediately.

Croque a l’Oignon Tart

For the onions:

1 and 1/2 pounds (3 medium) yellow onions, peeled, halved and sliced into 1/4-inch half-moons

2 fresh bay leaves

2 tablespoons canola oil

2 tablespoons unsalted butter, cut into cubes


Freshly ground black pepper

1/2 teaspoon chopped fresh thyme

For the Mornay sauce:

2 tablespoons unsalted butter

2 tablespoons flour

1/2 teaspoon salt

1/4 teaspoon freshly ground black pepper

Pinch grated fresh nutmeg

1 cup warm milk

1 cup grated Gruyere cheese

For the tart:

One 9-inch, prebaked tart shell, in its pan

3 ounces very thinly sliced Virginia or Black Forest ham

Prepare onions as in the French Onion Soup recipe, until they are golden brown and nicely caramelized.

Stir in the chopped thyme. Keep the onions warm on low heat if you are making the tart immediately; or cover and refrigerate for up to 3 days.

Meanwhile, make the Mornay sauce: Heat the butter in a small saucepan over medium heat until the butter bubbles. Whisk in the flour, salt, pepper and nutmeg, and cook for 2 or 3 minutes, to create a nutty-brown roux. Slowly whisk in the milk, beating constantly to prevent lumps. Cook the sauce for 2 or 3 minutes, until well thickened and bubbling. Remove from the heat and add the cheese, stirring until it is melted.

For the tart: Position a rack in the upper third of the oven and preheat the broiler to high. Line a baking sheet with aluminum foil.

Place the prebaked tart shell on the baking sheet. Spread the warm onions evenly in the bottom of the tart shell, cover with ham slices and top evenly with the Mornay sauce. Broil for 4 or 5 minutes, until the sauce is bubbling and nicely browned. Serve immediately.

You can also use techniques in these recipes for a wonderful sandwich.

Oniony Three-Cheese Croque-Monsieur

Onions prepared as for soup

Mornay sauce as prepared for tart (1 cup)

1/2 cup grated Gruyere cheese

1/2 cup grated Fontal cheese

8 slices country bread, about 7 inches across and 1/2-inch thick

4 tablespoons (a stick) unsalted butter, at room temperature

4 teaspoons Dijon-style mustard

1/2 cup caramelized onions

6 ounces Camembert cheese, cut into 1/4-inch- thick slices

8 ounces very thinly sliced Virginia or Black Forest ham

Make carmelized onions, as for soup. Make Mornay sauce, as for tart.

Position a rack in the upper third of the oven and preheat the broiler to high. Line a baking sheet with aluminum foil. Combine the Gruyere and Fontal cheeses in a small bowl.

Spread each slice of bread with butter on one side and mustard on the other. Place 4 of the slices in a large nonstick skillet, buttered side down. Top each slice with 2 tablespoons of caramelized onions, Camembert slices, ham slices and ¼ cup of the grated cheese mixture. Top each with a slice of bread, buttered side up.

Cook the sandwiches over medium heat until golden brown, 5 to 7 minutes, lightly pressing down on them with a spatula to ensure even toasting.

Carefully turn the sandwiches over and toast them on the second side until golden brown, 4 to 6 minutes. Transfer the sandwiches to the baking sheet and spread about ¼ cup of Mornay sauce over each one. Broil for 3 or 4 minutes, until the sauce is bubbling and nicely browned. Serve right away.