Mix all of the steamed bun dough ingredients together until it forms a shaggy ball. On a clean surface knead for 3-5 minutes until you have a uniform smooth ball, cover and rest for 1 hour. Make the red bean filling while you wait.
Divide the dough into 6 equal portions and roll into balls. Flatten and put about 1 ½ tablespoons of red bean paste into the center. Gather the edges of the dough together to seal the filling in to make a tight ball.
Line your steaming basket with a sheet of parchment paper cut into a circle with a few holes in it to allow steam through, place buns into steaming basket about 1 inch apart and let the buns rise for 30 minutes.
Heat up the steaming water and place the basket in the pan, place a cloth over the lid to collect the steam so it doesn’t drip onto the buns. Turn to medium low and steam for 15 minutes. Serve warm. These freeze great, to reheat wrap in a damp paper towel and microwave for 1 minute.
Red bean filling
Taste your red bean paste, add sugar to taste. Mix everything together in a small pan, cook for about 5 minutes stirring often to prevent sticking. The paste will caramelize and thicken, let cool.
Sticky rice cake dough
Slowly drizzle the water into the rice flour, only add as much water is needed so there is no dry flour left. Knead the dough a few times until the texture is consistent, the dough should be soft and tacky, not runny, add more flour if needed.
Divide the dough into 6 equal portions and roll into balls. Flatten and put about 1 ½ tablespoons of red bean paste into the center, pat down the paste. Gather the edges of the dough together to seal the filling in, softly pat between your hands to help seal it.
Wet your fingers and tap the buns so they become slightly moist, dry your hands and press each ball into the sesame seeds flattening it into a round patty, both sides should be pressed into the seeds, shake off the excess.
Heat a non stick skillet over medium heat, when hot turn down to medium low, add butter and the cakes. Cook for 3 minutes on each side until golden brown. Sprinkle with salt and serve warm.