Red bean paste is used as filling for many recipes: sweet cakes, steamed breads, sesame balls, dumplings and pancakes. It is made from adzuki beans, which have a sweet, nutty flavor when cooked. Add some sugar and a bit of butter to cooked adzuki beans, and you've got paste.
1 cup dried adzuki beans
2/3 cup sugar
1/4 cup unsalted butter
Soak beans overnight. Rinse, and cook them in a large pot of simmering water until soft, approximately 1 hour.
Drain and process in a blender until smooth. (If they aren't blending well, add a tsp or two of water)
Once smooth, spoon the paste into a saucepan, and cook over medium heat until thick, approximately five minutes. Add the butter and sugar, and cook over low heat, stirring constantly for about twenty minutes, until the paste is very thick, and starts to come away from the sides. Let cool to room temperature.
Here are a few recipes we've made that can use red bean paste as a filling:
Steamed buns, with a sweet filling. Can be made with red bean paste or sesame paste.
Tang Yuan, glutinous rice balls. The filling for these can also be red bean paste or sesame paste.
Red bean paste pancakes.