1 egg, lightly beaten
6 garlic cloves, minced
3 tablespoons dried oregano
1-1/2 teaspoons kosher salt
1 teaspoon pepper
1 pound ground lamb
1 pound ground beef
TZATZIKI SAUCE:
1 cup (8 ounces) plain Greek yogurt
1 medium cucumber, peeled, seeded and chopped
2 tablespoons lemon juice
2 garlic cloves, minced
1/2 teaspoon salt
1/4 teaspoon pepper
1/2 tablespoon finely chopped fresh dill (can substitute mint leaves for a slightly different version)
GYROS:
8 whole pita breads
3 tablespoons olive oil, divided
16 slices tomato
8 slices sweet onion, halved