Red Bean Filling - Easy Way
Wash one bag of small red beans (14 oz), put in pot and fill with triple amount water and boil for 10 min.
Place in a vacuum pot and leave overnight.
(If you don't have a vacuum pot, then simmer it, adding just enough water to cover as necessary, until cooked.)
The next day, use a hand held blender to blend the beans well.
Transfer to a wok and stir fry over high heat with 1 cup oil and 21/2 cups sugar until fairly dry.
Red Bean Filling - Hard Way
Cook red beans like above.
Put a colander in a bowl of water. Put small amounts of the red beans in the strainer and rub off the skins, letting the powdery liquid drain back into the bowl and discard the skins.
When all skins have been removed, strain the remaining liquid with fine mesh cloth or towel.
Discard liquid and the compact powder is the precious red bean residue to be fried with 3/4 cup oil and 2 cups sugar till it forms a sticky paste.