1 1/2 pounds ground chicken (light and dark meat)
4 slices Fontina cheese (optional)
1 teaspoon coarse salt
4 whole wheat hamburger buns
1/4 teaspoon freshly ground black pepper
Sliced tomato (optional)
1 teaspoon Dijon mustard
Sliced red onion (optional)
1/3 cup fresh bread crumbs
2 tablespoons fresh lemon juice
2 tablespoons chopped fresh chives
Preheat an outdoor grill or a grill pan to medium-high heat. Combine the chicken, salt, pepper, mustard, bread crumbs, lemon juice, and chives in a large bowl. Form into four ½-inch-thick patties.
Grill the patties, flipping once, until the juices run clear (the centre should register 160°F on an instant-read thermometer), 8 to 10 minutes. Top the patties with the cheese during the last minute of cooking, if using, and cover the grill to melt it.
Meanwhile, lightly grill the cut side of the buns, if desired.
Serve with any or all of the garnishes.