Grilled Chicken Spinach Burgers

1 pound ground chicken (you can always substitute lean ground beef)
1 cup frozen chopped spinach, thawed
1/2 cup crumbled feta cheese
1/2 teaspoon dried oregano
1/2 teaspoon garlic powder
1/2 teaspoon onion powder
1/4 teaspoon salt
1/4 teaspoon ground pepper
4 whole wheat rolls, split
12 thinly sliced cucumbers
8 thinly sliced red onions

1 tablespoon catsup
1/3 cup mayonnaise

Preheat grill to medium-high heat. Place thawed spinach in several paper towels and squeeze out extra liquid. Combine the chicken, spinach, feta, oregano, garlic and onion powders, salt and pepper. Mix well. Form into four 4" patties. Brush grill (or grill pan) with olive oil. Grill the patties until cooked through and no longer pink in the center (165°F), about 4 to 6 minutes per side. Place the burgers on buns, topping each with three cucumber slices and two onion rings. Whisk together the catsup and mayonnaise. Serve on the side or spread on buns.

To make ahead, prepare patties, wrap individually and refrigerate for up to eight hours. You can also freeze them. 

Also, if you don't have anything to "grind" the chicken, do what I do....place a chicken breast (one at a time) in a zip-lock bag. Pound with a mallet or a wide knife, turned on flat side. Pound until very thin. Take out and mince the thin chicken breasts. It works well.