This is the best Homemade French Onion Soup! It has a generous portion of caramelized onions in a rich, flavorful beef broth made from scratch. The cheese is broiled on top of croutons to melty, toasty perfection.
- ~1 cup caramelized onions [or the entire homemade recipe here]
- 1 tablespoon flour
- 1 tablespoon chopped fresh thyme (not packed)
- 2 tablespoons Cognac*
- 3 ½ cups beef broth [Preferably homemade or organic, low-sodium]
- Kosher salt and fresh cracked black pepper to taste
- French baguette, sliced ¾ inch thick along a diagonal
- 1 ½ cups (or more, I’m not judging.) gruyere, swiss and fontina cheese.**
- When making French onion soup, I caramelize my onions in a Dutch oven, so that I only dirty one pot. L-A-Z-Y
- Once your onions are sufficiently caramelized (deep, rich caramel in color) sprinkle with the flour and stir to coat. Add the thyme, Cognac, two large pinches kosher salt and a few grinds of pepper. Stir to distribute the spices and allow to cook on low for a few minutes.
- Add your beef broth and simmer over low heat for 30-40 minutes. This allows the flavors to develop.
- While your soup is simmering, toast your bread on a baking sheet under the broiler. Watch it carefully! Toast until brown on each side.
- Ladle an equal amount of soup into each broiler-safe, 13 ounce bowl. Top with several bread slices and then top with ¼ of the cheese mixture. Broil on a baking sheet until the cheese has melted and has started to bubble and brown.
- Serve immediately, but eat with care! HOT!
*Cognac is brandy that has been made in Cognac, France. It is like the Champagne of brandy. You can taste the difference. The higher the quality, the better the taste of your soup. Since there is such a tiny amount in this recipe, you could buy those small airplane bottles or a pint. If Cognac is not an option, then opt for the best brandy you can afford.
**I used almost a cup of gruyere and then an overflowing ¼ cup each of fontina and swiss. You do your thing.
***My husband wanted more broth. I like it as written. If you know you would like a thinner soup (fewer onions in each bite) then increase your beef broth to 4 1/2 cups. As long as you are using quality beef broth, this should not impact the flavor too much. Feel free to throw in a little extra thyme and Cognac.
Based on a recipe by Martha Stewart