Onion soup gratinated with Jarlsberg fits excellent for cold winter days. Turn regular soup into a culinary treat by adding toasted bread with grated Jarlsberg to the soup and gratinate in a preheated oven for 10 minutes.
Simmer the onions in a casserole in the butter on low heat for 30 minutes until the onions have a golden caramelized colour and taste. Add chicken stock and thyme. Simmer for 15 more minutes. Taste with salt and pepper. Pour the soup into soup portions bowls and put toasted bread into the soup and grated Jarlsberg on top. Gratinate in a preheated oven for 10 minutes.