Preheat your grill or stovetop grill pan over medium-high heat.
Season the chicken breasts with salt, pepper, garlic powder, onion powder, dill, lemon zest, and half of the lemon juice. Drizzle with olive oil and rub the mixture evenly over the chicken.
Grill the chicken for about 6-7 minutes per side, or until the internal temperature reaches 165°F. Remove from the grill and let it rest for 5 minutes before slicing.
While the chicken is resting, prepare the quinoa according to package instructions if not already cooked.
In a large bowl, combine the cooked quinoa, cherry tomatoes, cucumber, red onion, feta cheese, and olives. Drizzle with the remaining lemon juice and toss gently to combine.
Slice the grilled chicken and serve it over the quinoa salad. Garnish with fresh parsley.