preheat oven to 350°F.
mix all dry ingredients together in a large bowl. then, make a well in the center.
add all wet ingredients to the well. whisk together to form a smooth and runny batter, scraping down sides with a spatula as needed.
lightly grease an 8 inch square or circular cake tin with coconut oil. then, pour batter into the pan.
plop mashed red bean paste into the batter, one small spoonful at a time, making sure to distribute the red bean paste evenly in the pan.
generously, and evenly, sprinkle the shredded coconut on top to finish
bake in the middle of the oven for 50-60 minutes, rotating once halfway through. the cake is done when the top of the cake is lightly golden brown and the center is no longer jiggly.
when complete, turn off the oven and leave the oven door slightly ajar and let the cake sit for 10 minutes. afterwards, let cool on cooling rack for at least an hour before cutting!