Can you make red bean paste from bean flour?

Question

I was having a conversation with someone about making a dessert from red bean paste and they mentioned the process being arduous because they had to cook the beans for two hours, and then mash them.

I knew that bean flours like besan is commonly used in cooking flatbreads in Indian cuisine, and those are made by grinding down chickpeas - something that takes hours to cook normally, gets reduced to five minutes as a flour.

Since red bean paste seems to be made by boiling beans and then mashing them, would the same step in reverse work? That is, grind them down to a flour first and boil them to form a porridge, as that should take far less time.

Secondary question: what is the difference between porridge and a paste, in this contex? Does cooking the beans and mashing them produce a different result from grinding them down and boiling the flour? (My intuition tells me no, but I'm not a chef)

Answer 1

Yes, it's possible and in fact sometimes done in Japan, but doing so creates a specific type of red bean paste called sarashi-an (晒し餡, "dried/bleached paste") that is only used in a few recipes, primarily soups.

More broadly, Japanese bean pastes are usually categorized by their texture. The three types mostly commonly used in Japanese confectionery, pastries, desserts and cakes are tsubu-an (粒あん), which is simply boiled beans; tsubushi-an (潰し餡) which is boiled and mashed; and the most common, koshi-an (漉し餡), which is boiled, mashed and sieved to remove the skins. These have a range of textures and flavors that simply can't be replicated by using powdered beans. And if time or efficiency are a concern, you don't need to boil your own, since you can easily and cheaply buy ready-to-use bean paste in cans or shelf-stable bags in any Japanese grocery.