Onion Soup Gratiné

Ingredients

• 1  baguette 
• 1 tablespoon flour all-purpose
• 1 pound gruyère cheese shredded
• 8 cups beef broth low-sodium
• 1 tablespoon olive oil 
• 0.5 teaspoon salt 
• 1 teaspoon sugar 
• 4  thyme sprigs 
• 7 tablespoons butter unsalted divided
• 1 cup white wine 
• 3 pounds onions yellow thinly sliced

Equipment

• bowl
• baking sheet
• oven
• pot

Directions

1. Melt 4 Tbsp. unsalted butter and 1 Tbsp. olive oil in a large pot.
2. Add 3 lb. thinly sliced yellow onions and 4 thyme sprigs; cook, covered, on medium-low heat for 20 minutes, stirring often.
3. Uncover, add 1 tsp. sugar and 1/2 tsp. salt. Cook, stirring often, until onions are deep brown and caramelized, 30 to 40 minutes.
4. Add 1 Tbsp. all-purpose flour; cook for 2 minutes more, stirring.
5. Add 1 cup white wine and 8 cups low-sodium beef broth; stir up browned bits on bottom of pot. Lower heat and simmer for 30 minutes; stir occasionally. Season with pepper.
6. Preheat oven to 425F.
7. Cut 1 baguette into 8 thick slices.
8. Spread both sides with 3 Tbsp. unsalted butter; place on a baking sheet. Toast until golden on both sides, 5 to 8 minutes, turning over once.
9. Fill 8 bowls with soup.
10. Place a slice of toast on top of each bowl. Divide 1 lb. shredded Gruyre on top. Set bowls on baking sheets; bake until cheese is bubbly, 5 to 10 minutes.