Chop the onion in a food processor. In a medium bowl, mix the turkey breast, onion, garlic powder, onion powder, cumin, cilantro, salt, pepper and egg.Heat a grill or medium nonstick sauté pan to medium heat. Lightly coat the grill or pan with cooking spray. Form the burger mixture into two 4-ounce patties. If the mixture is too wet, add the panko.Place the patties on the grill or in the pan and cook approximately 5 minutes on each side or until they reach an internal temperature of 160°F. Remove the patties from the heat and let rest until reaching a temperature of 165°F.Serve the turkey burger patties on whole wheat buns with your choice of condiments.