My Secret for the Best French Onion Soup Recipe

Ingredients

• 3 tablespoons unsalted butter (45 ml), plus more for greasing ramekins
• 3 tablespoons olive oil (45 ml)
• 3 large yellow onions, thinly sliced (about 3 lbs / 1.36 kg)
• 1 teaspoon granulated sugar (5 ml)
• 1/2 teaspoon kosher salt (2.5 ml), plus more to taste
• 1/4 teaspoon freshly ground black pepper (1.25 ml), plus more to taste
• 2 cloves garlic, minced
• 1/4 cup dry sherry (60 ml)
• 8 cups beef broth (2 liters), low sodium preferred
• 2 sprigs fresh thyme
• 1 bay leaf
• 6 slices baguette, about 1 inch thick
• 1 clove garlic, halved
• 8 ounces Gruyère cheese, shredded (about 2 cups / 225 g)