In a small bowl, combine cumin, coriander, smoked paprika, cinnamon, cloves, cayenne pepper, salt, and black pepper. Mix thoroughly until well combined. This homemade shawarma seasoning is what gives your sheet pan chicken shawarma its authentic taste, so don't skip making it fresh. Pro tip: Mix your spices in a small jar and shake vigorously for better distribution. This ensures no one bite is overly spicy while another is bland.

Cut chicken thighs into 2-inch pieces and place in a large mixing bowl. Add 2 tablespoons olive oil, fresh lemon juice, minced garlic, and all of your shawarma seasoning blend. Toss everything together until the chicken is evenly coated. Pro tip: Don't be afraid to get your hands in there and massage the marinade into the chicken—this helps the spices penetrate the meat for maximum flavor.

Cover the bowl with plastic wrap and refrigerate for at least 30 minutes, though up to 4 hours is even better. This marinating time allows the flavors to develop and helps tenderize the chicken. Pro tip: If you're short on time, even 15 minutes makes a difference, but the longer you marinate, the more flavorful your baked chicken shawarma will be.

While the chicken marinates, prep your vegetables. Cut the red bell pepper into 1-inch chunks, cut the onion into similar-sized pieces, and halve the baby potatoes. Toss these vegetables together in a separate bowl with the remaining 1 tablespoon of olive oil and a light sprinkle of salt and pepper. Pro tip: Cut your vegetables to uniform sizes so they cook evenly on your sheet pan. This prevents some from being overcooked while others are still crunchy.

Preheat your oven to 425°F. Line your sheet pan with parchment paper or lightly oil it. Spread the marinated chicken pieces across the pan in a single layer, then arrange the prepared vegetables around the chicken, nestling them between the pieces for even heat distribution. Pro tip: Leave a little space between pieces rather than crowding everything together. This allows hot air to circulate and ensures everything roasts rather than steams.

Place the sheet pan in the preheated oven and roast for 25-30 minutes, stirring the vegetables and turning the chicken pieces halfway through cooking (around the 15-minute mark). The chicken is done when it reaches an internal temperature of 165°F and the edges are slightly caramelized. Pro tip: Don't skip the stirring step! This ensures even cooking and helps develop those beautiful caramelized edges on both the chicken and vegetables. It's what separates a good one pan shawarma from a great one.

While the chicken roasts, prepare your tahini sauce by whisking together tahini, lemon juice, minced garlic, salt, and warm water. Start with 4 tablespoons of water and add more gradually until you reach a drizzle-able consistency—it should be creamy but pourable. Pro tip: If your tahini sauce seizes or becomes too thick, don't panic. Just add water one tablespoon at a time while whisking. It'll come back together beautifully.

Remove the sheet pan from the oven and let it rest for 3-5 minutes. Transfer the chicken shawarma to a serving platter, drizzle generously with tahini sauce, and garnish with fresh parsley and mint if desired. Serve immediately with warm pita bread, rice, or your favorite sides. Pro tip: The residual heat will continue to cook the chicken slightly, so don't overcook it in the oven. A little pink near the bone in the thighs is actually fine since thighs are more forgiving than breasts.