Step 1: Soak 2 1/2 cup adzuki bean overnight;
Step 2: Strain and remove water, transfer to rice cooker. Add water (at least twice the volume of soaked adzuki bean). Heat under "cook" mode to bring to boil, switch to "warm" mode, cook until beans are tender and can be easily mashed;
Step 3: Stand sieve on a large mixing bowl with enough water, strain cooked beans portion by portion, mash beans so that bean paste can pass through sieve and skins of red bean are separated and left in sieve;
Step 4: Strain adzuki bean paste / water suspension through jelly strainer bag, squeeze paste as dry as possible;
Step 5: Heat wok under medium powder;
Step 6: Add 100 mL oil into hot wok, stir in adzuki bean paste;
Step 7: Stir until water in the paste evaporates completely and paste turns into dry powder;
Step 8: Add 2 cup sugar and stir vigorously, making adzuki bean powder evenly covered with melted sugar and thus, turns back into paste in a dark brown color;
Step 9: Transfer adzuki bean paste to a container. Let cool to room temperature and store in the freezer. Defrost to room temperature before using.
* 2 1/2 cup dry red bean can give 8 cup adzuki bean paste.