Ingredients:

• 3 large onions
• 4 tablespoons butter 
• 1/2 teaspoon thyme
• 1/2 cup sherry 
• 6 cups beef stock
• 1 French baguette
• 2/3 pound Gruyere cheese (Emmantaler or Swiss)
• 1/3 pound mozzarella cheese
• salt and pepper to taste

Directions:

1. Slice 6 pieces of bread (use a good loaf about as round as your bowls) about 1 inch thick, and toast them at 250 for 15-20 minutes. Grate the cheese and slice the onions thin while the bread is cooking.
2. Add of butter to a large pot and melt over medium heat. Add the onions. Cook the onions until soft and browned. This will take about 25-30 minutes. If they are cooking too fast turn the heat down to low.
3. Add the thyme and a sprinkle of black pepper. Mix with onions for 1 minute.
4. Pour the sherry into the onions and stir. Allow sherry to reduce and caramelize for 5-10 minutes.
5. Once bread is done toasting, remove the bread and raise the temperature to broil. 
6. Pour beef stock into the onions. Turn heat to high and simmer for 10-15 minutes. Taste and add salt and additional thyme and black pepper as desired.
7. Pour soup into bowls. (It’s a good idea to place them in a tray so you can take them all out at once). Add toast to the top of each bowl. Top with mozzarella cheese and then Grueyre cheese. 
8. Place carefully in the oven for 1-3 minutes, or until cheese browned and crispy around the edges. Remove from oven and serve.