1: Slice the scotch bonnet, garlic, and onion.
2: Mince the shadon beni / culantro finely.
3: In a bowl, mix the tomato ketchup, sliced scotch bonnet, garlic, onion, shadon beni, salt, black pepper, lime juice, sugar, and water.
4: Adjust sugar to your liking.
5: Serve the sauce with fresh oysters.