The origin of adzuki beans has always been a bit of a mystery, but researchers from Taiwan and Japan analyzed almost 700 samples from across Asia and found that the beans were first domesticated in central Japan, somewhere between 3000 and 5000 years ago. RECIPE FOR ANKO BEAN PASTE 200g adzuki beans 130g sugar Parboil beans 5 minutes, drain. Simmer for 1 hour or until soft. Use a drop lid to prevent beans from moving while boiling. Reserve some of the cooking liquid, drain beans. Puree in a food