This was absolutely one of my all time favourite fillings, black bean paste, it had addicting bakery aroma, they just tasted like heavenly, slightly aroma, and average sweet, wasn't too sweet and better balance. It commonly called 豆沙 is a sweet bean paste often used as a filling in mooncakes, sticky rice cake or steamed bun with red bean paste in many Chinese desserts.
3/4 cup adzuki beans
4 cups cold water
2 pieces chinese brown sugar
or 1 cup granulated sugar
25g slightly salted butter
1 tbsp corn flour + 2 tbsps cold water
stir well and set aside.
1) Wash the beans, and soak for 30 minutes, drain beans and discard water.
2) Place beans in a casserole, add 4 cold water and bring to a boil over middle heat, cook for about 1 hours and 30 minutes. add sugar and pour corn flour and water to make the red bean soup become very thick paste.
3) Allow to cool completely and blend on high speed until they are smooth.
4) Heat up the pan, then add butter and the red bean mixture, reduce heat to middle low, stir fry the bean paste until thicken, repeat the process in 3 - 4 times, and of course patience, stirring constantly, until thickened, about 1 hour.
5) Store in a bowl or container with covered, in the fridge until ready to use; it will keep well for 5 days or freezer up to 12 days. To allow them soften in the room temperature. Refreezing not advised from either a safety or quality point of view. Divide the red bean paste into 16 portions of rough balls.
If you don't inclination to stand at the stove for 1 hour to pan fried red bean paste, then you'll have to come back every 15 to 20 minutes for repeat the stirring process.
Recipe Source: JosephineRecipes.Co.Uk