In a bowl, toss chicken thighs with cumin, coriander, paprika, turmeric, salt, and 1 tablespoon olive oil until evenly coated. Let sit at room temperature while you prep everything else, or refrigerate up to 4 hours ahead.

Combine rinsed rice, chicken broth, and salt in a small saucepan. Bring to a boil, then reduce heat to low, cover, and simmer for 15 minutes. Remove from heat and let steam, covered, for 5 minutes. Fluff with a fork.

Heat remaining 1 tablespoon olive oil in a large skillet over medium-high heat until shimmering. Add chicken in a single layer and cook undisturbed for 4-5 minutes until deeply browned and slightly charred. Flip and cook 3-4 minutes more until cooked through. Work in batches if needed to avoid crowding.

In a small bowl, stir together minced garlic, mayonnaise, and lemon juice until smooth. Taste and adjust with more lemon if desired. This shortcut version delivers that classic shawarma shop flavor without the emulsion work.

Divide rice among four bowls. Top with seared chicken, diced cucumber, and cherry tomatoes. Drizzle generously with garlic sauce and sprinkle with fresh parsley. Serve with warm pita on the side if desired.