French Onion Soup with Pretzal Croutons

• 4 tablespoons Butter
• 4 large onions, thinly sliced
• 2 tablespoons sugar
• Salt and pepper to taste
• 6 cups good beef stock or canned broth
• 2 tablespoons dry sherry
• 4 large, hard sourdough pretzels, broken into bite-sized croutons
• 1 cup grated Gruyere Swiss cheese

Directions
Melt butter in large saucepan. Add slices onions and cook until transparent, about 20 minutes. Add sugar to onions and cook 10 more minutes. Add salt, pepper, stock, and sherry. Cook another 30 minutes. Preheat the broiler. Portion the soup into oven-proof bowls. Top with pretzel pieces and sprinkle cheese over top. Place under broiler until cheese melts.