Soak bamboo skewers in water for at least 30 minutes before putting meat on. Cut pork into ½ thick x 1 inch wide x 1 ½ inch long pieces. Slide pork onto skewers and set aside.

In a large bowl combine soy sauce, garlic, onion, juice of 2 lemons, 7-UP, ground black pepper, dark brown sugar and ketchup. Using a whisk mix and dissolve ingredients really well and pour marinade mixture onto the pork. Cover and set in the fridge at overnight or at least a 4 hours before grilling. Grill on direct heat until pork is done.