My mom comes from Sasayama, a tiny country town within the Hyogo Prefecture, which is part of the Kansai region. Although the town is small, population +/- 44,000 persons, Sasayama is known throughout Japan for their kuromame (black beans), adzuki (red beans), wild boar, chestnuts, Matsutake mushrooms, and yams.
Similar to eating black-eyed peas on New Year’s Day and Rosh Hashanah, Japanese people eat kuromame as part of osechi ryori, an elaborate “bento box” meal specifically made just for New Year’s Day. The meal represents a wish for long life, health and energy during the upcoming year. So one might assume that if one had extra large black beans, one might have even more health and prosperity in the New Year, right? Well, the black beans from Sasayama are extra jumbo large, like an inch-long so they are extremely coveted for their part in osechi ryori. The black beans are considered to be the best in Japan, and not just by people from Tamba. Mom said a 200-gram bag (about two cups) might fetch $16. That’s a whole lotta beans for a handful of beans.
The trick to getting them ink black is to cook them in a cast iron pot. Since my mom didn’t bring an iron pot with her from Japan 40+ years ago when she moved to this country, she uses nails to get the same effect and she’s been using the same nails ever since. Whether you use nails or an iron pot, iron leaches into the water and a chemical reaction occurs, giving the beans their distinctive tar black color and very, very slight metallic taste.
The next time you plan on making black beans, take a trip to the hardware store first. Tell them you’re making beans - can they suggest a box of nails that would compliment the meal?
You’ll need either a handful of iron nails (about a cup) or a cast iron pot to achieve super dark beans.
KUROMAME (Japanese Black Beans)
Makes 2 cups, serves 8-12
1-cup dried kuromame
3 cups water
3/4-cup sugar
1/2-teaspoon salt
1/2-teaspoon baking soda
2 tablespoons soy sauce
If using nails, tie them up in a piece of cheesecloth. Set aside.
In a 3-quart saucepan, rinse the kuromame in cold water, checking for debris. Drain and add back to the saucepan. Add the water, sugar, salt, baking soda and soy sauce. Mix well. Add the bundled nails, cover, and let sit overnight at room temperature.
Place the saucepan over medium heat. When it comes to a boil, reduce heat to the lowest setting possible. Cover the surface with aluminum foil (to help trap heat and moisture) and cook until the beans are tender, between 4-6 hours. Be sure to keep the beans covered in liquid. If the liquid gets too low, add additional water to cover. Cool to room temperature and remove nail bundle. Serve beans drained of liquid but store extra beans in cooking liquid to keep moist. Enjoy!
Rinse and dry nails and cheesecloth to store.