In a large bowl, combine turkey, egg, salt, pepper, onions and parsley. Stir gently with spatula to combine or use hands. Do not overwork or burgers will be tough. Refrigerate for one hour before cooking

Preheat indoor griddle to medium high heat. Divide meat into 4 patties. Cut butter into about half tablespoon pats. Press butter into center of each patty and form meat around it.

Spray griddle with cooking spray before adding burgers. Cook about 4 minutes per side or until brown and cooked through. Add melted cheese, if desired, by placing a slice on burgers and covering with a pot lid for a minutes.

Place on cooked burger on bun along with desired toppings. For even more fun, try this super easy avocado spread shown below.

Spread:

Combine 1/2 avocado, 3 Tbs. mayonnaise, the juice of 1 lime, and 1/4 teaspoon salt in medium bowl; mash until smooth. Spread on bun before adding turkey burger.