In a large bowl or food safe container, add 1 tablespoon golden syrup, 1 tablespoon rice wine, 2 teaspoons light soy sauce, 1 teaspoon dark soy sauce, 3 tablespoons hoisin sauce, 2 tablespoons tomato ketchup, 1/4 teaspoon Chinese 5-spice, 1/2 teaspoon smoked garlic powder, 1/2 teaspoon MSG, 1/4 teaspoon beetroot powder, dash sesame oil and 2 tablespoons water. Mix well. Prod 1 pork tenderloin fillet a few times with the tip of a sharp knife and add to the prepared marinade. Mix well to coat, cover and set aside in the fridge for 1 hour, or overnight if possible. Remove from the fridge 20 minutes before cooking.