1 (3 oz.) can Parmesan cheese
1/2-3/4 c. mayonnaise
1/8 c. grated onion
1/2 tsp. garlic salt
Sm. loaf party rye bread
Fresh or canned mushroom slices, drained

Mix and spread on party rye. Garnish with mushroom slices. Broil, being careful not to burn.