Preheat the oven to 375º F.
Place the chicken breasts in a large bowl with the sliced onions and drizzle with olive oil. Add the lemon zest, lemon juice, za'atar, paprika, oregano, garlic, salt, and pepper. With bare clean hands, toss the chicken and rub the oil and herbs into the chicken until evenly coated. Transfer the chicken breasts and onions to a sheet pan and drizzle any leftover liquids from the bowl over the chicken. Bake for 25-30 minutes, or until the chicken is cooked through with an internal temperature of 165º F.
While the chicken is baking, prepare your naan and pine nuts. Spread hummus over each naan, then top with a handful of salad greens. Cut the reserve lemon half into wedges and squeeze fresh lemon juice over the greens.
Place your pine nuts into a dry pan over medium-low heat. Give the pan a shake and toss the pine nuts every few minutes to prevent burning. Once the pine nuts are golden brown and aromatic, remove from heat and set aside.
Once the chicken is done, remove from oven. Transfer the chicken to a cutting board and roughly chop the chicken into bite-sized pieces. Place the chicken into a bowl along with the pine nuts, pomegranate arils, and chopped parsley. Give it all a good mix, then top each naan with a generous amount of the chicken mixture.
Serve, and enjoy! (This dish is great when the chicken is hot out of the oven, lukewarm, or even cold. If it's summer and you want to turn this into a more refreshing and cooling dinner, cook the chicken in advance and refrigerate it for a few hours before mixing it with the pine nuts, pomegranate, and parsley. Then top the naans whenever you're ready.)