French Onion Soup

1. Melt Butter and Cook Onions

Start by melting the butter in a Dutch oven over medium heat. Once it's fully melted and starting to bubble, stir in the onions, 1 teaspoon of salt, and the sugar. Cook this mixture for about 20 minutes, stirring occasionally. The onions will begin to release their liquid and turn uniformly translucent, which is your cue to move to the next step.

2. Caramelize Onions

Uncover the pot and continue cooking the onions for another 5 to 10 minutes. This allows the liquid to evaporate. Afterward, keep cooking the onions for an additional 30 to 40 minutes, stirring frequently. During this time, the onions will caramelize, turning a rich caramel color that adds depth and sweetness to the soup.

3. Add Wine and Broth

Next, pour in the red wine and stir, scraping up any browned bits from the bottom of the pot. Cook for about a minute until the wine has mostly evaporated. Then, add the beef broth, thyme sprigs, bay leaves, ½ teaspoon of pepper, and ½ teaspoon of salt. Bring the soup to a boil, then reduce the heat and let it simmer gently for 30 minutes.

4. Prepare Croutons

While the soup simmers, preheat your oven to 350 degrees Fahrenheit. Toss the baguette cubes with the olive oil, remaining ¼ teaspoon of salt, and remaining ¼ teaspoon of pepper on a rimmed baking sheet. Bake the croutons for 15 to 18 minutes until they are golden and crisp.

5. Finish and Serve

When the soup has finished simmering, remove and discard the thyme sprigs and bay leaves. Taste the soup and adjust the seasoning if needed. Preheat your oven to 500 degrees Fahrenheit and set up six ovensafe crocks on a rimmed baking sheet. Divide the soup among the crocks, then top each with a generous handful of shredded Gruyère and Parmesan cheeses, followed by a few croutons. Place the baking sheet in the oven and bake for 5 to 7 minutes, until the cheese is melted and bubbly with a hint of golden brown. Let the soup cool for about 5 minutes before serving to ensure it's not too hot to enjoy.