Cheese Puffs

1 C. water
2 Tbsp. butter
1/2 tsp. salt
1/8 tsp. cayenne pepper
1 C. all-purpose flour
4 eggs
1 1/4 C. shredded Gruyere or Swiss cheese
1 Tbsp. Dijon mustard
1/4 C. grated Parmesan cheese

In a large saucepan, bring water, butter, salt, and cayenne to a boil. Add flour all at once and stir until a smooth ball forms. Remove from heat, immediately transfer to a mixing bowl. Add eggs, one at a time, beating well after each addition. Continue beating until mixture is smooth and shiny. Stir in Gruyere or Swiss and mustard.
Drop by rounded teaspoonfuls 2 inches apart onto a greased baking sheet. sprinkle with Parmesan cheese. Bake at 425 degrees for 15-20 min. or until golden brown. Serve warm.