Zenzai (Sweet Red Bean Soup with Mochi)

To Make the Zenzai with Dried Azuki Beans (for 4–6 bowls)

1. Gather all the ingredients.

Option 1: Pressure Cooker Method

1. Rinse 1 cup azuki beans carefully until the water runs clear. Discard any damaged beans that are floating. Drain the water and transfer the beans to a pressure cooker (I use an Instant Pot).
2. Add 4 cups water. Cover and lock the lid. Make sure the steam release handle points at Sealing and not Venting.
3. Turn on your pressure cooker. For an Instant Pot, select Manual or Pressure Cooker mode, choose High pressure, and set the cooking time to 15 minutes (or 10 minutes for slightly firmer beans).
4. For a stovetop pressure cooker, cook on high heat until it reaches high pressure. Then, reduce the heat to low to maintain the pressure for 15 minutes.
5. When it’s done cooking, the Instant Pot will switch automatically to the Keep Warm mode. (For a stovetop pressure cooker, remove the pot from the heat.) Let the pressure release naturally for 30 minutes. Then, turn the steam release handle to Venting to release any remaining pressure. Open the lid.
6. Add 1 pinch Diamond Crystal kosher salt (to taste) and ¾–1 cup sugar into the pot.
7. Cook on low heat (select the Sauté function on the Instant Pot) for about 5 minutes, stirring occasionally, until the sugar dissolves completely.
8. After cooking for 5 minutes, the soup will be a bit darker in color. Keep it warm while you prepare the mochi (see below for instructions).

Option 2: Stovetop Method

1. Rinse 1 cup azuki beans carefully until the water is clear. Discard any damaged beans that are floating, then drain the water.
2. Put the azuki beans and 4 cups water in a pot.
3. Bring the water to a boil over medium-high heat. Once boiling, put an otoshibuta (drop lid) on top of the beans. Turn down the heat to medium low and keep it simmering, without the pot lid, for the next 1–1½ hours. Tip: The otoshibuta will prevent the beans from dancing around too much. You can make your own with aluminum foil.
4. Some liquid will evaporate, so add water as needed to keep the beans submerged. After 1 hour, pick up a bean and mash it with your fingers. If it mashes easily, it‘s done. Otherwise, cook for another 15 minutes and check again. Add ¾–1 cup sugar and 1 pinch Diamond Crystal kosher salt (to taste) and cook over low heat, stirring occasionally, until the sugar dissolves completely. Keep it warm while you prepare the mochi (see below for instructions).

To Make the Zenzai with Prepared Red Bean Paste (for 1 bowl)

1. To a small saucepan, add ½ cup sweet red bean paste (anko) that‘s either store bought or homemade. I used tsubuan (chunky paste) here, but you can use koshian (fine paste) if you prefer. Add ½ cup water. Bring it to a boil. Add 1 pinch Diamond Crystal kosher salt to taste and mix well. Adjust the consistency by adding water or reducing the soup. Keep warm while you prepare the mochi (see the next step).

To Prepare the Mochi

1. To make bite-size pieces of kirimochi, cut 4 pieces Japanese rice cake (mochi) into halves or quarters. Put the pieces on a wire rack set in a baking sheet, then place in a toaster oven or regular oven. You can also toast in a frying pan. If using fresh homemade mochi or shiratama dango, add it to the soup to warm it up. If using frozen mochi, heat it in a pot of boiling water until soft.
2. Toast the dried mochi until puffed up and nicely brown, about 10–12 minutes.

To Serve

1. Serve the red bean soup in individual bowls and add the toasted, fresh, or boiled mochi. Enjoy!

To Store

1. Transfer the soup to an airtight container and store in the refrigerator for up to 4 days and in the freezer for up to a month. Prepare the mochi right before you serve the Zenzai.