Thaw frozen banana leaves at room temperature. Or, quickly thaw them under cool running water. Rinse banana leaves to remove any dirt or dust. Pat dry with paper towel or cloth kitchen towel.
If necessary, remove thick rib that runs down the center of banana leaf. Use scissors or sharp knife to cut banana leaf to fit baking vessel.
Use kitchen tongs to hold banana leaves. Pass over an an open flame (such as gas stove burner) several times until banana leaf is shiny and deep green. Repeat will all banana leaves. Set aside. NOTE: This is make the banana leaf more pliable and easy to work with. Be careful not to burn the banana leaf.
Grease giant muffin tin with melted butter. Press banana leaf into muffin tin cavity to line the mold. Brush banana leaf with melted butter. Set aside and prepare batter.
Preheat oven to 375°F (190°C).
Sift together rice flour, all-purpose flour, baking powder, and salt in a medium bowl. Set aside.
In a large bowl, whisk eggs until yolks are broken. Add sugar. Use an electric hand mixer or a sturdy whisk to beat eggs and sugar until smooth. Add coconut milk and melted butter. Beat together until well combined.
Add half of dry rice flour mixture. Stir to combine. Add remaining rice flour mixture. Mix until batter is smooth and there are no dry streaks of flour.
Add 1/2 cup portions of batter into prepared giant muffin tin. Bake for 20 minutes. Add slices of cream cheese on top of each bibingka. Bake for another 10-15 minutes until cakes are set and toothpick inserted in cake comes out clean.
Unmold bibingka from giant muffin tin. Bibingka is best served warm, fresh from the oven.