- Wash the red beans and soak in water for at least 8 hours.
- Rinse, then boil them with fresh water (make sure the water level remains above the beans) in a pot or a high-pressure cooker until they are soft (about 1.5 hours for a pot, 40 minutes for a high-pressure cooker).
- Pour out the water and reserve for a red bean dessert soup. Set the beans aside to cool (or if you want to speed things along, put the pot in an ice bath). Once the beans have cooled, you can optionally filter out the skins if you wish by pushing the beans through a sieve. Blend everything in a food processor.
- Transfer the resulting paste to a saucepan and add the sugar, butter, and salt. Cook at a simmer while continuously stirring the paste, until any excess water has been cooked off. Let the paste cool before using.
I ran across this while looking up how to make moon cakes - one of my favorite Chinese traditional desserts - from the site China Sichuan Food. I had to read quite a bit between the lines on some instructions, and making it the first time was definitely an experiment, but it was all worth it. Not only do I get to tailor exactly how sweet my red bean fillings should be (the original recipe called for 2 cups - way too much for my taste!) but the leftover red bean "soup" can then be lightly sweetened and drunk as a separate dessert soup. Win-win!
Part of the reason I started baking was because I like my goodies to be less obviously sweet - I want to taste the flavor, not just the sugar. So most of these recipes will have the sugar dialed down.