Whisk together all-purpose flour, baking powder, baking soda, and salt in a bowl, forming a well in the center.
Add to the center of the dry ingredients sugar, plant-based milk, oil, apple cider vinegar, vanilla extract, and coconut extract (if desired), and whisk together to form a smooth thick batter.
Divide the batter into three separate bowls. Mix the cocoa into one portion, the pandan extract into one portion, and leave the last portion plain.
Lightly oil your baking molds with neutral-tasting oil, use cupcake wrappers, or line your steaming trays or molds with parchment paper.
Pour the dark-colored batter into the bottom, the plain batter in the middle, and the pandan-colored batter on top in each tray or mold. Optionally sprinkle the tops with a light dusting of vanilla sugar or vegan caster sugar.
With your steamer over medium heat (don't let the water boil fully), steam the bolu kukus for 20-25 minutes until the centers have risen. It's totally ok, and some people like it even more when the kukus naturally split open. Allow them to cool for ten minutes, slice, and enjoy your layered Roti Kukus!