Onion Soup with Sage Brown Butter, Croutons, and Grated Lemon Peel Recipe | Epicurious

Ingredients

• 12 tablespoons (1 1/2 sticks) butter, divided
• 24 cups thinly sliced onions (about 5 3/4 pounds)
• 8 cups (or more) low-salt chicken broth
• 1 1/2 cups 1/2-inch pieces torn crustless country-style bread
• 16 fresh sage leaves
• 1 1/2 tablespoons (or more) Sherry wine vinegar
• 2 teaspoons finely grated lemon peel