Preheat broiler to high heat. Line a large rimmed baking sheet with foil and spray with oil or cooking spray.

In a large bowl, add ground meat, egg, parsley, dried onion, salt, pepper, and cinnamon. Mix together gently with hands to distribute the seasonings, being careful not to over-mix.

Divide mixture into eighths and pat each into an oblong disc, about ½-inch thick. Place patties on prepared sheet pan, leaving space in between.

Add tomatoes and onions to the open space around the meat patties and drizzle with olive oil. Season everything on the sheet pan with salt and pepper.

Transfer sheet pan to the oven and broil for 8 minutes. Flip the meat patties over and broil for another 5 minutes.

Serve in pita bread as sandwiches with feta cheese and cucumbers or alongside cooked basmati rice with mast-o-khiar if desired. Sprinkle everything with ground sumac for even more Persian flavor!