Begin by cutting the yellowfin tuna into bite-sized cubes. This will ensure even cooking and allow the fish to absorb all the wonderful flavors of the curry.
In a large pot, heat a tablespoon of oil over medium heat. Add the sliced onion and sauté until translucent. Then, add the crushed ginger, garlic, and cumin seeds. Cook until fragrant, about 2-3 minutes.
Next, introduce the cardamom, turmeric powder, dry red chilies, and the Maldivian chili. Stir well to coat the onions and let the spices bloom for a minute.
Gently fold the cubed tuna into the pot, ensuring that the pieces are evenly coated with the spice mixture. Cook for about 5 minutes until the tuna is slightly opaque.
Add both the thick coconut milk and the light coconut milk to the pot. Stir well to combine all the ingredients, making sure the tuna is submerged in the creamy sauce.
Now, add the curry leaves and the strips of coconut leaf (or rampe leaf). These will impart a unique flavor to the curry. Season with salt to taste.
Lower the heat and let the curry simmer for about 15-20 minutes, allowing the flavors to meld together. Stir occasionally to prevent sticking.
Finally, stir in the scraped fresh coconut just before serving. This adds a delightful texture and enhances the coconut flavor.
