Prepare pork: Trim 2 pounds pork loin or tenderloin, removing fat and silver skin. Cut into 1½ to 2-inch cubes. Place in large bowl. If using wooden skewers, soak in water 30 to 45 minutes.

Make marinade: Whisk together BBQ sauce, honey, brown sugar, soy sauce, tomato paste, garlic powder, onion powder, black pepper, red pepper flakes, and optional pineapple juice and smoked paprika until smooth. Remove ⅓ of marinade (about ½ cup) to small saucepan for basting. Set aside.

Marinate pork: Pour remaining marinade over pork cubes and toss to coat. Cover and refrigerate 4 to 8 hours, flipping halfway through.

Thread skewers: Remove pork from refrigerator 20 to 30 minutes before grilling. Thread pork tightly onto skewers with minimal gaps. Discard used marinade.

Prepare grill and glaze: Set up two-zone fire with one side medium-high (400-425°F) and other side indirect heat. Simmer reserved marinade over medium heat for 5 to 7 minutes until thickened. Keep warm.

Grill skewers: Place skewers over direct heat. Grill 2 to 3 minutes per side, rotating to char all sides, 8 to 12 minutes total. Move to indirect heat and cook until internal temperature reaches 140-145°F, another 6 to 10 minutes.

Glaze and finish: During last 2 to 3 minutes, brush skewers generously with thickened glaze on all sides. Remove when internal temp reaches 145°F. Rest 5 minutes tented with foil.

Serve: Garnish with cilantro or green onions. Serve with extra glaze for dipping. Pork should be juicy with sticky, glossy exterior.