Mix the coconut milk, curry paste, eggs, fish sauce and seafood together in a bowl. Half-fill a wok or steamer pan with water, cover and bring to the boil over a medium heat.
Cut out a long sliver, about 1 cm (½ inch) width, from each of the romano peppers. Remove the seeds and membrane from each 'case', then clean and dry them. Place a few basil or spinach leaves or some shredded cabbage in the bottom of each pepper case. Spoon the seafood mixture into each pepper, almost to the top. Place on a plate that fits in a bamboo steamer basket or on a steamer rack inside the wok. Cover and steam for 15–18 minutes.
Meanwhile, mix the flour and reserved coconut milk in a small saucepan until smooth. Stir and cook over a medium heat for 2–3 minutes or until thick. Spoon a little of it on top of the peppers. Garnish with kaffir lime leaves and chilli slices and serve with boiled rice or cooked noodles.