In a large bowl combine the rice flour, glutinous rice flour, sugar, baking powder, and salt. Whisk until combined.
Add the water, coconut milk, butter, and eggs until smooth. Cover and refrigerate overnight.
Rinse banana leaves under warm water and wipe of any dirt. Use scissors to trim thick edges and cut into 12 squares big enough to cover one space on your muffin tin. Quickly pass leaves over stove flame for a couple of seconds to soften.
Place the leaf square over the tin and use a small cup to gently press the leaf into the tin to hold shape. Carefully ladle enough batter over the leaf, filling it up to just below the top. Repeat until all 12 are filled.
Place a dollop of cream cheese in each cake. Top with a slice of egg in each. Bake for 25 minutes, or until an inserted toothpick comes out clean.
Remove from oven and spread butter on top. Sprinkle with coconut. Serve hot.