Slow Cooker French Onion Soup - Kikkoman Home Cooks

Ingredients

• 6 medium sweet white onions, sliced to ¼ inch thickness
• 4 tablespoons unsalted butter
• 6 cups low-sodium beef stock
• ¼ cup Kikkoman® Rice Vinegar
• 3-4 tablespoons Kikkoman® Soy Sauce
• 2 sprigs thyme
• 1 dried bay leaf
• ¼ teaspoon cracked black pepper
• For Serving
• 1 French bread baguette, sliced into ½ inch slices
• 1 ½ cups shredded gruyere cheese