Step 1 Put the cheese, tomato soup, Worcestershire sauce, onion and pepper in a skillet. Stir over medium heat until the cheese is thoroughly melted.
Step 2 Remove the skillet from the heat for 1 to 2 minutes for the cheese mixture to firm up slightly. Ladle the mixture onto the slices of toast and broil until the tops start to bubble -- but don't let them brown. Garnish with the chives. Serve hot.