Prepare the dry rub by combining all ingredients. Rub into all sides of the pork tenderloin and set aside.
Prepare the honey sriracha sauce by combining all ingredients. Set aside.
Preheat grill (charcoal or gas) to 400°. (If your charcoal grill doesn't have a thermometer, just preheat coals like you normally would until they are hot. Charcoal should be on the next to lowest setting.)
Coat grill grates with a high-heat cooking spray. (Use caution, as you might get some flame flare-ups).
Grill pork about 2 minutes per side on direct heat. (Medium heat if using a gas grill.) Close the lid of the grill while cooking.
Move the pork slightly off of direct heat and cook for about 4 minutes on each of the two larger sides. (If using a gas grill, just reduce heat to medium-low). Close the lid of the grill while cooking.
Place a large piece of aluminum foil on the grill on indirect heat. Spray with high-heat cooking spray. Transfer the pork to the foil. Baste generously with the sauce. Cook for about 4 minutes with the lid closed.
Turn the pork and baste generously with more of the sauce. Close the foil slightly to make a tent. Grill for about another 4 minutes with the lid closed.
Check the temperature of the pork. Once it reaches 140°, transfer the pork to a cutting board. Cover with foil and let rest for about 10 minutes.