Preheat outdoor grill (or grill pan, if cooking indoors) to medium-high heat.
In a large bowl, combine chicken, salt, pepper, mustard, breadcrumbs, lemon juice, and chives and form into four 6-ounce patties.
Grill patties 8-10 minutes, flipping once, until juices run clear (160 degrees on a meat thermometer). Top patties with cheese during last minute of cooking and cover grill (or grill pan) to melt.
Lightly grill cut side of buns if desired. Serve with optional garnishes.
These were delicious and easy to make--And they tasted a lot better than a turkey burger! We used gruyere instead of fontina cheese, and it was delicious. Do NOT make the baked potato poppers that are featured on the same episode--We made them and they were awful!