In a large bowl, whisk together the all-purpose flour, mochiko flour, baking powder, and baking soda. Set aside.
In another bowl, whisk together the coconut milk, eggs, ube extract (optional), and melted butter until combined. If you have the ube jam, add it to this mixture. Set aside.
Gradually add the dry ingredients to the wet mixture, gently stirring. The batter doesn’t need to be perfectly smooth; it’s okay if some lumps remain.
Preheat a medium-sized (12-inch) pan over medium heat. Test readiness by sprinkling a few drops of water—if they evaporate immediately, the pan is ready.
Spray some oil into the pan to coat it lightly. Using a ladle, pour a quarter of the batter into the pan.
After about 2 minutes, when bubbles form on the surface and the edges are set, flip the pancake. Cook for another 2 minutes, then remove from the heat.
Continue cooking the remaining batter, repeating the process for each pancake.