If using wooden skewers, soak them in water for 1 hour. Thread the pork belly slices onto skewers in a spiral shape, starting from one end and working to the other.
Prepare curry marinade: Mix the curry powder with 3 tablespoons of oil.
Prepare paprika marinade: Mix the paprika powder, dried marjoram, and pepper with 3 tablespoons of oil.
Coat the skewers generously with the marinades. Cover and refrigerate for 2 to 3 hours.
Preheat oven to 200°C (392°F). Roast the skewers on a baking tray for 20 to 25 minutes, turning once halfway through. The pork should reach an internal temperature of 63°C (145°F). Sprinkle with salt.
Monitor carefully during cooking — the meat should have crispy edges but not be dark and hard. If using a grill instead of an oven, reduce cooking time slightly.
Transfer to a serving plate and garnish with fresh parsley.