Simmered Thick Fried Tofu (Atsuage Nimono)

Steps

1. 1
   Cut one block of atsuage crosswise into four triangular pieces. Repeat with the second block.
2. 2
   Bring water to a boil in a pan, add the atsuage, and simmer for about 5 minutes until soft and tender. Drain well.
3. 3
   Clean the pan and return the atsuage to it. Add water, mirin, and sugar. Bring to a boil over medium heat and simmer for 2 minutes, turning occasionally.
4. 4
   Add dashi powder and soy sauce, stir well, and return to a boil. Reduce to low heat, cover with a drop-lid (or foil), and simmer for 10 minutes total, flipping halfway through.
5. 5
   Add vinegar and mix well. Remove from heat and let cool completely with the lid on to allow flavors to fully infuse. Reheat gently before serving.