*Note: The beef/chicken broth ratio was an “oops” moment I had once and the soup turned out so freaking delicious, I never changed the ingredients. I’m sure you can make it 6 cups of beef broth and it’ll be just fine!!! Use what you have, but I strongly advise all or mostly beef broth.
4 average-size sweet onions, sliced thin
3 T butter
1 T vegetable oil
1/2 tsp. sugar, plus more if needed
1 1/2 cups chardonnay
4 cups low-sodium beef broth
2 cups low-sodium chicken broth
A few sprigs of fresh thyme, tied together with kitchen string
2 bay leaves
Baguette, torn or cut into pieces
Gruyère cheese block, sliced thin
2 1/2 T dry sherry (optional but highly recommended)
In your dutch oven or large pot over medium-high heat, melt the butter. Add the vegetable oil and onions and sautée them 10-15 minutes or until they start to shrink. They will shrink!
Turn the heat down to medium and add some S&P (you can always add more later) and the sugar. Using a wooden spoon or wooden spatula, stir and caramelize. This is the most important step. If you rush it or ruin it, you should start over or order pizza. I LOVE this how to for caramelizing onions. It takes absolute patience but it pays off in the end! Do not cheat this step!
Once the onions are done, add the white wine and up the heat. Cook, stirring occasionally, until all of the wine has evaporated.
Add the thyme sprigs, bay leaves, and beef/chicken broths. Bring your pot to a boil and then reduce the heat to low. Let it simmer, uncovered, at least 45 minutes.
I like this soup better once all the flavors have had time to incorporate. When I make it and eat it the same day, I like it to have as much time to simmer as possible. 3-4 hours is ideal, although you can have this ready in 90 minutes if you’re in a rush.
If you’re letting it sit: remove the thyme, bay leaves, and adjust S&P after 2 hours. Continue to let it simmer another couple hours.
If you’re in a rush: remove the thyme, bay leaves, and adjust S&P after 45 minutes. Get ready to serve.
Within 10 minutes of serving, add the sherry and stir well. The sherry is totally optional but it gives the soup a bite and there’s definitely a difference between beef broth with and without sherry! TRUST ME!
To assemble: Put a few small pieces of bread into the bottom of a bowl. Ladle some soup in the bowl and top with a couple slices of cheese. Put the bowl under the broiler for a few minutes until the cheese is bubbly and brown.