Heat olive oil in a pan and sauté onions, garlic, and spices for two minutes.
Combine the cooled onion mixture with pork mince, fat, sage, and eggs in a bowl.
Mix the ingredients thoroughly and season with salt and pepper.
Shape the mixture into four patties approximately 2-3 cm thick.
Cook patties in a pan over medium heat for three minutes per side until done.
Preheat the grill to a hot temperature.
Grill pineapple for one minute, top with Gruyère, and grill 30 seconds more to melt.
Toast the bun halves on both sides.
Layer rocket, tomato, pork burger, and cheesy pineapple onto each bun base.
Mix mayonnaise with chopped chilli and drizzle over the burgers before serving.