For the sticky pork marinade, combine all the ingredients in a large bowl.
Add the pork to the marinade, season with salt and pepper and toss well to coat. Cover and place in the fridge for at least 2 hours or overnight for best results.
When ready to cook, preheat the barbecue grill to medium hot and lightly grease with the oil.
Alternately thread the pork, pineapple and onion pieces onto the prepared skewers, being mindful not to squeeze too much onto each skewer to allow proper cooking (the ingredients should only be lightly touching each other).
Grill the skewers for 6 7 minutes, turning and basting with the marinade every now and then, until golden brown and caramelised on the outside and cooked through to your liking. Transfer to a wooden board, cover loosely with foil and leave to rest for 5 minutes.
While the skewers are resting, increase the barbecue grill to hot.
Place the lime halves, cut-side down, on the grill and char for 1 2 minutes on each side or until caramelised with lovely char lines.
Divide the skewers among plates, scatter over the coriander and serve with the charred lime.