In a medium bowl, combine the orange juice and zest, lime juice, soy sauce, olive oil, sugar, cumin, chili powder, garlic and cilantro for the marinade. Whisk together until well-combined.
Place the chops in a large resealable plastic bag and pour the marinade in on top. Seal the bag and turn to coat well. Allow to sit at room temperature for 30 minutes to an hour. If you would like to marinate longer, refrigerate for up to 3 hours, but bring it back to room temp before grilling.
Preheat your grill or grill pan over medium-high heat, remove the pork chops from the marinade – reserving the marinade – and cook for 3-5 minutes per side, or until internal temperature reaches 165 degrees C.
Meanwhile, place the reserved marinade in a small saucepan over medium-high heat. Bring to a boil and then reduce to a simmer for about 5 minutes (or more if necessary) until reduced and slightly thickened.
Serve chops with a spoonful of sauce (or in a bowl for dipping.)