2 large yellow onions, peeled and thinly sliced
1/2 teaspoon garlic powder
2 packets stevia or 1 tablespoon sugar substitute of choice
8 cups (two 32-ounce containers) beef broth
4 tablespoons grated parmesan cheese
8 thin slices swiss cheese
1/2 teaspoon dried thyme
2 tablespoons balsamic vinegar or Worcestershire sauce
pinch salt and pepper (to taste)
1. Spray a large pan with nonstick cooking spray. Add your sliced onions and 1 cup beef broth and garlic powder. Sauté onions until the broth is completely evaporated, and onions begin to caramelize.
2. Add the onions and the remaining ingredients, including Parmesan cheese, to the slow cooker. Cook in the slow cooker on high for 4 hours, or on low for 8 hours.
3. When ready to serve, ladle soup into an oven safe bowl, and add a piece of Swiss cheese on top. Place in oven preheated to low broil to melt the cheese. Leave in oven for 1-3 minutes, or until cheese is lightly golden brown. Optional: Add croutons to the bowl before ladling the soup into the bowl.