Mix the marinade: In a large bowl, whisk the yogurt, olive oil, garlic, lemon juice (and zest if using), cumin, coriander, paprika, turmeric, cinnamon, black pepper, salt, and cayenne. The mixture should be thick but spreadable.
Prep the chicken: Pat the chicken dry. If using breasts, pound to an even ½-inch thickness so they cook evenly.
Add the chicken to the bowl and coat thoroughly. Work the marinade into every nook.
Marinate: Cover and refrigerate for at least 30 minutes. For best flavor, 4–12 hours is ideal. If you’re short on time, even 20–30 minutes helps.
Choose your cooking method: Skillet: Heat a large skillet over medium-high. Add a thin film of oil.
Cook thighs 5–6 minutes per side (breasts 4–5 minutes per side), until browned and cooked through.
Oven: Preheat to 425°F (220°C). Arrange chicken on a lined sheet pan with sliced red onion. Roast 18–22 minutes, until the thickest part reaches 165°F (74°C).
Broil 1–2 minutes at the end for extra char.
Grill: Preheat to medium-high and oil the grates. Grill thighs 5–6 minutes per side (breasts 4–5), turning once, until nicely charred and cooked through.
Rest and slice: Transfer to a cutting board and rest for 5 minutes. Slice into thin strips across the grain for that shawarma-style bite.
Build your plate: Pile the chicken into warm pita with crunchy veggies and your favorite sauce, or serve over rice with a big salad. Finish with fresh herbs and a squeeze of lemon.