|Onion||1 Small, chopped|
|Horseradish mustard||3 Teaspoon|
Place slices of the bread on broiler pan, 3 inches from heat.
Broil for 5 minutes or until toasted on one side.
Combine the hamburger and egg in a mixing bowl, then add the remaining ingredients and mix thoroughly.
Spread thinly over untoasted side of bread.
Broil until edge of bread is slightly brown and hamburger mixture is done.