Whisk first 5 ingredients in a stainless steel mixing bowl.
Add ground beef, breadcrumbs and feta, mixing gently to combine.
With water moistened hands, form mixture into 4 — 3/4" patties.
Grill over medium-high heat with lid closed for 4 minutes each side, or until an instant-read thermometer indicates a Food Safe internal temperature of 160° F (70° C).