• In a small jar with a tight-fitting lid, combine lime zest, lime juice, honey, salt, and garlic powder. Cover and shake to combine. 
• Place half the marinade in a covered container and refrigerate until serving time. Pour remaining half marinade into a 1-gallon zipper-top plastic bag. Add chipotle pepper and mash to combine. 
• To plastic bag, add pork tenderloin bag and seal, removing as much air as possible. Place in the refrigerator for 6 to 24 hours, rotating the bag halfway through the time. 
• Remove the tenderloin from the bag and rest at room temperature while preparing the grill. Remove the reserved marinade from the refrigerator.

To cook on a charcoal grill:

• Fill a large chimney starter with natural lump charcoal and light.  Once the charcoal is ashy and white, approximately 30 minutes, dump the hot charcoal onto the lowest grate of the grill and spread into an even layer using extra-long tongs. Place the cooking grate back on the grill and cover with the lid; heat the grate to medium heat for 2 to 3 minutes. 
• Brush the grill with vegetable oil. Remove the tenderloin from the bag and place in the center of the grate. Discard the bag with marinade. Cover and cook for 12 to 15 minutes, turning every 1 1/2 to 2 minutes, until the tenderloin reaches an internal temperature of 140 degrees.
• Remove the tenderloin from the grill and place on a large piece of heavy-duty aluminum foil folded at the edges to create a basket, and pour on the reserved marinade. Wrap tightly and rest for 10 minutes. Remove to a cutting board and slice. Garnish with cilantro and serve. 

To cook on a gas grill:

• Preheat the grill over medium-high heat. Clean and oil grate. Remove the tenderloin from the bag and place in the center of the grate. Discard the bag with marinade. Cover and cook for 12 to 15 minutes, turning every 1 1/2 to 2 minutes, until the tenderloin reaches an internal temperature of 140 degrees.
• Remove the tenderloin from the grill and place on a large piece of heavy-duty aluminum foil folded at the edges to create a basket, and pour on the reserved marinade. Wrap tightly and rest for 10 minutes. Remove to a cutting board and slice. Garnish with cilantro and serve.