Chikuzenni  or Nishime is a classic Japanese dish often served on New Year's Day, but my mom used to make it quite regularly because it was my family's favorite Nimono (it means "simmered dish" like Nikujaga).  This is also a popular side dish for bento because it can be made in advance and still tastes great at room temperature.

Chikuzenni (Nishime) – Simmered Chicken and Vegetables

INGREDIENTS

• ¾ lb boneless skinless chicken thighs (12 oz, 340 g)
• ½ Tbsp sake (for marinating chicken)
• ½ Tbsp soy sauce (for marinating chicken)
• 6 dried shiitake mushrooms (1 oz, 30 g)
• 1 cup water (240 ml; for rehydrating dried shiitake mushrooms)
• 1 lotus root (renkon) (6 oz, 180 g)
• ½ gobo (burdock root) (4 oz, 110 g)
• 1 Tbsp rice vinegar (separated; for soaking lotus root and gobo)
• 5 Satoimo (Japanese Taro) (9 oz, 250 g)
• ½ boiled bamboo shoot (3 oz, 90 g)
• 1 carrot (6 oz, 170 g)
• ½– 1 block konnyaku (konjac) (4.5 oz, 130 g)
• 10 snow peas (1 oz, 30 g)
• ⅛ tsp salt (kosher or sea salt; use half if using table salt) (for blanching snow peas)
• 1 ½ Tbsp sesame oil (roasted) (separated)

Seasonings:

• 2 cups dashi (480 ml)
• 3 Tbsp sake
• 3 Tbsp mirin
• 1 Tbsp sugar
• 3 Tbsp usukuchi (light-color) soy sauce (or use 2 Tbsp soy sauce + ⅛ tsp salt)
• ½ tsp salt (kosher or sea salt; use half if using table salt)

INSTRUCTIONS

1. Gather all the ingredients.
2. Remove extra fat of the chicken and cut into 1 1/2 inch pieces. Marinade in 1/2 Tbps. sake and 1/2 Tbsp. soy sauce and set aside.
3. In a small bowl, put dried shiitake mushrooms and 1 cup water and soak for 20-30 minutes, or until tender. Squeeze the liquid out from the shiitake mushrooms and strain the liquid (roughly ¾ cup).
4. Cut the shiitake mushrooms into hexagon, which represent turtle shape for longevity.
5. Cut the lotus root into Hana Renkon. Cut them into ⅛ inch (3 mm) slices and soak them in water (2 cups water + ½ Tbsp vinegar).
6. Cut the bamboo shoot in half and thinly slice.
7. Peel the taro and cut in half and sprinkle some salt to get rid of sliminess.
8. Rub the taro with hands and wash them in running water.
9. Scrape the skin off the burdock root with the back of the knife. After rinsing, cut it into thin slices. Quickly soak them in water (2 cups water + ½ Tbsp vinegar).
10. Cut the carrot into Nejiri Ume. Blanch half of them for 2 minutes and reserve for decoration.
11. Cut the konnyaku into Tazuna Konnyaku.
    
12. Pull the strings at the seams of the snow peas and discard them. These are tough and not edible. Boil water in a saucepan over high heat. Add pinch of salt and blanch the snow pea pods for 30-60 seconds, until crisp but tender enough to eat.
13. Remove the snow peas from the water and transfer to the iced water to stop cooking and set aside. In the same boiling water, add konnyaku. After boiling again, cook for 2-3 minutes to remove the smell.
14. Cut the blanched snow peas in half and set aside.
15. In the large pot, heat 1 Tbsp of sesame oil over medium-high heat. When it’s hot, cook the chicken until it turns white. Transfer the chicken to a plate.
16. Add ½ Tbsp sesame oil and cook all the ingredients except the blanched snow peas and carrots that are reserved for decoration.
17. Add dashi stock and shiitake mushroom liquid.
18. Bring it to a boil. Skim off the fat and scum that accumulates on the surface.
19. Add sake, mirin, sugar, soy sauce, and salt.
20. Add the chicken back into the pot.

    
21. Bring it to a boil. As you see, the stock should cover about 80% of the ingredients.
22. Make Otoshibuta and cover the ingredients. Cook for 10 minutes.
23. Remove Otoshibuta and cook for another 10 minutes. Taste and adjust seasonings if needed.

To Serve and Store

1. Add the snow peas and remove from the heat. Cover, and let cool. Serve Chikuzenni in a dish or traditional Japanese lacquer container, “Ju-bako”. Top with the snow peas and blanched carrots.

https://www.justonecookbook.com/chikuzenni-simmered-chicken-and-vegetables/