"This is a denser version of the traditional banana cake and is very easy to make. You can either steam it in a square baking tin, in individual foil cups or do it the traditional way, in banana leaves."
Toss the coconut with 1/4 teaspoon salt in a bowl; set aside.
Sift the rice flour, tapioca flour, and arrowroot starch together in a large bowl; stir the coconut cream into the mixture until the flours are incorporated into the cream, at least 10 minutes. Stir the sugar into the mixture until completely dissolved. Add the mashed banana and mix well. Add 1/8 teaspoon salt and coconut milk; again, mix well. Pour the batter into a square baking tin or individual aluminum foil cups. Top with the reserved coconut.
Bring about 1-1/2 inches of water to boil in a steamer fitted with a large basket. Steam the cake over the boiling water until cooked through, 20 to 25 minutes.