Direction

1. Make patties: Place garlic cloves in a small skillet over medium-high heat; toast until spotty brown, about 5 minutes. Peel, mince, and set aside.
2. Break up lamb in a medium bowl. Sprinkle with minced toasted garlic, feta, oregano, salt, and pepper; stir with a fork to combine. Divide into 4 equal portions. Toss each portion back and forth between cupped hands to form a ball. Pat with fingertips to flatten to about 4-inches wide. Refrigerate patties.
3. Make sauce: Mix together cucumber, sour cream, mint, vinegar, and garlic in a small bowl until combined. Season with salt and pepper. Refrigerate until ready to serve.
4. Cook patties: Build a hot fire on one side of the grill. Replace the rack. When coals are covered with white ash, place patties on the rack and close the lid. Cook on the preheated grill until done, about 4 to 5 minutes per side for medium to medium-well burgers. An instant-read thermometer inserted into the center of patties should read at least 160 degrees F (72 degrees C). Remove patties to a plate to rest.
5. Toast pitas on the hot grill until spotty brown and warm, about 1 minute per side. Split toasted pitas crosswise. Spread about 2 tablespoons sauce over 4 pita halves. Top each with a red onion slice, a tomato slice, and a burger patty. Spread remaining sauce over each burger. Top with remaining pita halves.