Tamarind water, to soften, or substitute with the juice of 2 lemons
In a bowl season the fish with salt, pepper, lime juice, and betutu paste.
On a sheet tray, lay down the banana leaf. Place a salam leaf on the banana leaf. Place the fish on the middle of the banana leaf over the salam leaf. Place sliced green tomatoes, lime leaf, sweet basil, and tamarind water on the fish. Season with salt and pepper.
Wrap the fish folding both ends together and secure with a bamboo skewer. Grill until cooked, approximately 4 to 5 minutes per side depending on the thickness of the fillets.
Grind shallots, garlic, tumeric, ginger, galangal, lemongrass, chili peppers, palm sugar, and shrimp paste in a food processor. Saute paste with coconut oil.