Step by Step method

1. Step 1.

   Combine ¼ cup plain Greek yogurt, grated cucumber, ½ teaspoon minced mint, ½ minced garlic, and ⅛ teaspoon table salt in bowl; cover and refrigerate tzatziki until ready to serve. Break up 12 ounces ground lamb into small pieces in bowl then add ½ teaspoon cinnamon,⅛ teaspoon pepper, remaining garlic, and remaining ½ teaspoon salt. Lightly knead with hands until combined. Pinch off and shape mixture into six ½-inch-thick patties.

2. Step 2.

   Heat 1 teaspoon oil in 12-inch nonstick skillet over medium-high heat until just smoking. Add patties and cook until well browned on first side, about 4 minutes. Flip patties, reduce heat to medium, and cook until well browned on second side and tender throughout, about 4 minutes. Transfer to paper towel–lined plate.

3. Step 3.

   Cut top 2 inches from 1 pita; discard or reserve for other use. Place pita on plate, cover, and microwave until warm, about 30 seconds. Spread half of tzatziki inside pita, then fill with half of lettuce, sliced cucumber, tomato slices, and lamb patties. Serve. (Remaining lamb patties, tzatziki, and prepped vegetables can be refrigerated, separately, for up to 24 hours.)