Enjoy the taste of high-end traditional Japanese restaurants (ryotei). These are best with a chewy texture, perfect for osechi (the traditional Japanese New Year's feast). These low sugar treats can be made in either a pressure cooker or regular pot.
Kuromame, preferably from the Tanba-Sasayama region
Sugar (light brown sugar)
Soy sauce (regular or usukuchi soy sauce)
Salt (a pinch)
Disposable tea filter
Rinse off the rusted nails, and put them in an empty tea bag.
Put the seasoning and water in a sauce pan, add the nails, bring to a boil. Rinse, then add the kuromame and bring to a boil. Turn off the heat, and let sit for about 10 hours.
Heat the beans after letting them soak overnight, bring to a boil, then carefully skim the surface scum. If the water boils down, add more. The beans should always be immersed in water.
Cover with a drop lid, then the pot lid, and simmer for about 8 hours over very low heat. If the liquid boils down, add no more than about 100 ml water at a time.
When the beans become tender, stew until the water just covers the beans. Then they're done.
In Step 4, if using a pressure cooker, heat until the low-heat pressure gauge rises, and turn off the heat when it starts to move. Then the beans are done.
If using a regular pot, they must stew for a long time, so if you need to step away from the pot, turn off the heat. Once you're ready to get back to the stove, you can continue to stew the beans.
If possible, let the beans soak overnight again in the liquid. The flavor will be nicely absorbed. The beans should be stored in the liquid as well.
Story Behind this Recipe
This is my mother-in-law's recipe. The symbolic auspicious meaning of serving the beans at new year's meals is to give those who partake a long life well until the skin wrinkles from age, so actually, hard and wrinkled beans are symbolically more appropriate; however, when using kuromame from Tanba, this is the way to prepare them. Apparently, it's the way they are prepared at high-end traditional Japanese restaurants. Although the beans are expensive, it's a nice way to end the year, and a perfect way to honor my mother-in-law's signature recipe.
Since the beans must never be above the liquid when simmering, add water from time to time. This method of stewing prevents the beans from wrinkling, and gives them a springy texture. The standard addition of baking soda was omitted here because it sometimes leaves a bitter taste. Some beans do not produce scum. The beans turn out not so sweet with 60 g of sugar; I use 65 g.