In a bowl, whisk together the oil, curry paste, hot mustard, granulated mustard, maple syrup, soy sauce, teriyaki sauce, lime juice, ground peppercorns, dried rosemary, dried thyme, and minced garlic until combined. Add chilli flakes if you prefer a spicier flavor.
Put the pork medallions in a sealable freezer bag and pour the marinade over them. Seal the bag and massage gently for 1 minute to coat all sides.
Refrigerate for at least 8 hours.
Heat a grill or grill pan to medium-high heat. Grill the pork medallions for 3–4 minutes per side until the internal temperature reaches 63°C / 145°F.