Soupe à l’oignon

Name: Soupe à l’oignon (Onion Soup)
Cuisine: French
Ingredients: 6 large yellow onions, sliced thin; 2 tablespoons sugar; ⅛ teaspoon pepper; 7 cups chicken stock; ¼ pound butter; 1 teaspoon salt; 2 tablespoons flour; Grated Gruyère or Parmesan cheese; 2 onions, sliced; 6 (½-inch thick) slices French bread; Chunk of butter