Toss chicken thighs with shawarma seasoning and 1 tablespoon olive oil until evenly coated. Let sit at room temperature while you prep the remaining ingredients.

Heat remaining 1 tablespoon olive oil in a 12-inch skillet over medium-high heat until shimmering. Add chicken in a single layer and cook undisturbed for 4 minutes until deeply browned. Flip and cook 2 minutes more. Transfer to a plate; chicken will not be fully cooked through yet.

Reduce heat to medium. Add onion to the skillet and cook 3 minutes, scraping up any browned bits, until softened. Add garlic and orzo; toast for 2 minutes, stirring constantly, until orzo turns golden and smells nutty.

Pour in chicken broth and lemon juice, stirring to combine. Nestle the partially cooked chicken and any accumulated juices into the orzo. Bring to a simmer, then reduce heat to low, cover, and cook 12-14 minutes until orzo is tender and liquid is absorbed. Remove from heat and let stand covered for 5 minutes.

Fluff the orzo with a fork. Dollop Greek yogurt over the top and sprinkle with fresh dill and parsley. Serve directly from the skillet, dragging the yogurt through each portion.