Lamb Kofta Gyros

Ingredients

• 12 ounces ground American lamb
• 1 small red onion
• 2 cups quartered cherry tomatoes
• 15 ounces chickpeas, drained and rinsed
• 1/2 seedless cucumber, quartered lengthwise and chopped into triangles
• 2 tablespoons red wine vinegar
• 2 tablespoons extra-virgin olive oil
• Kosher salt
• 1/2 cup loosely packed mint leaves
• 2 tablespoons finely chopped fresh parsley
• 2 tablespoons dry bread crumbs
• 2 garlic cloves, minced
• 1 teaspoon Aleppo pepper or other mild chile powder
• 8 wood skewers, soaked at least 30 minutes in water
• 1/2 cup Greek yogurt
• 4 pitas, warmed on the grill