Classic French Onion Soup
- 3 pounds yellow onions, cut into 1/8-inch pieces
- 3 tbsp unsalted butter
- 1/2 tsp salt, plus more if needed
- 1 pinch of sugar
- 1 tbsp all purpose flour
- 8 cups of water
- 1 sprig fresh thyme, or 1/2 tsp. dried thyme
- 1/4 cup dry white wine
- 1 crusty baguette
- 8 ounces gruyere cheese (I used swiss because that is what I had on hand)
- Melt butter in a large dutch oven or soup pot over medium heat. Add the onions, salt and sugar and cover and cook for 10 minutes.
- Take the cover off and cook, stirring frequently, the onions for 90 minutes. Yes, 90 minutes. You should achieve a golden brown color to the onions.
- At this point, stir every 5 minutes and add a tbsp. of water at a time to loosen up the brown bits at the bottom of the pan. Continue doing this for another 30 minutes until the onions are even darker brown.
- Add the flour and stir for 1-2 minutes.
- Add the 8 cups of water and thyme and bring to a boil. Then add the white wine then let simmer for 10 minutes. Add salt, to taste.
- In the meantime, turn on the broiler in your oven and adjust the rack to the upper middle position. Slice your baguette into 3/4 inch thick slices.
- Carefully broil the baguettes for 1-2 minutes on each side (or until they achieve a light brown crisp color - watch them carefully so they don't burn). Remove from oven and set aside.
- At this point you can start ladling in your soup into oven-safe bowls. Place a slice of baguette on top and a large slice of gruyere cheese on top of the baguette slice. Place the bowls carefully into the oven under the broiler and broil until cheese has melted and is bubbly and slightly brown, about 5 minutes.
- Let cool for 5 minutes before serving. Be very careful with the bowl and make sure to not touch it while eating your soup!
- Store leftovers in an airtight container in the refrigerator.