Awesome Spinach and Feta Turkey Burgers

I sometimes buy turkey burgers at Whole Foods flavored with spinach and feta, and I decided recently I could make them just as well on my own. I made this recipe tonight for 4th of July and we grilled them outside. They were so good I want to write down what I did, since I improvised. No photos - they were gone too quickly to document.

Spinach and Feta Turkey Burgers

1 package lean ground turkey (not turkey breast) - about 20 ounces
Breadcrumbs from 1 slice wheat bread
Egg white, slightly beaten
2 ounces crumbled feta cheese (half a normal sized container)
5 ounces fresh spinach (half a bag)
1 small Vidalia onion, finely chopped
1 garlic clove, minced
1 generous slug Worcestershire sauce
ground pepper

Saute onion and garlic until soft. Chop the spinach and mix with the onion and garlic mixture until wilted but still bright green. Mix with ground turkey, breadcrumbs, feta, egg white, generous slug Worcestershire sauce and pepper. Form into burgers and refrigerate for a couple hours, otherwise it will stick to the grill.