If using wooden skewers, soak for at least 30 minutes in water.
In a large bowl, add pork shoulder cubes, garlic, paprika, sugar, salt, pepper and vegetable oil. Toss well to combine. Cover and refrigerate for a minimum of 20 minutes.
Preheat the oven to broil. Set the rack on highest setting (so that the top of the skewers will be about 5 – 6” below the broiler). Line a baking sheet with foil and lightly grease with 1 tsp vegetable oil.
On each skewer, thread on alternating pieces of pepper, pork and pineapple as shown above. Sprinkle a pinch of cayenne pepper over each pineapple piece.
Place onto baking sheet and season with salt and pepper. Broil for approximately 5-6 minutes until pork browns and pineapple lightly caramelizes. Carefully turn the skewers to evenly broil the other sides until pork is evenly browned and cooked through, 3-4 minutes per side.
Transfer to a plate. Cover with foil and let rest for 5 minutes before serving.