Vidalia Onion Soup - The Local Palate

Ingredients

• 6 tablespoons butter
• 6 medium-large Vidalia onions, peeled and thinly sliced
• 10 cups beef stock
• 1 bouquet garni (a couple sprigs each of thyme, parsley, and rosemary, and 2 bay leaves tied together with kitchen twine)
• ⅓ cup cognac or sherry
• Salt and pepper to taste
• 6 slices day-old sourdough bread
• 4-6 ounces gruyère or sharp cheddar, grated