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Slow-Cooker Miso Soup With Shiitakes and Sweet Potatoes

By Meaghen Walsh

Published on October 15, 2019

Time

4 to 6 hours on low or 3 to 5 hours on high

Yield

Serves 6

Slow cooker size

4 to 7 quarts

Slow-Cooker Miso Soup With Shiitakes and Sweet Potatoes

Ingredients

12 ounces shiitake mushrooms, stemmed and sliced thin2 scallions, sliced thin1 (2-inch) piece ginger, peeled and sliced into ¼-inch-thick rounds4 garlic cloves, minced2 teaspoons toasted sesame oil Salt and pepper ⅛ teaspoon red pepper flakes 6 cups water ½ cup white miso 14 ounces extra-firm tofu, cut into ½-inch cubes12 ounces sweet potatoes, peeled and cut into ½-inch pieces1 tablespoon soy sauce, plus extra for seasoning3 ounces (3 cups) watercress, cut into 2-inch pieces

Before You Begin

You can substitute firm tofu here if desired; avoid silken, soft, or medium-firm tofu, as these varieties will break down while cooking.

Instructions

  1. 1. Microwave mushrooms, scallions, ginger, garlic, oil, ¼ teaspoon salt, and pepper flakes in bowl, stirring occasionally, until mushrooms are softened, about 5 minutes; transfer to slow cooker.
  2. Whisk 1 cup water and miso in now-empty bowl until miso is fully dissolved. Stir miso mixture, tofu, potatoes, soy sauce, and remaining 5 cups water into slow cooker. Cover and cook until potatoes are tender, 4 to 6 hours on low or 3 to 5 hours on high.
  3. Discard ginger. Stir in watercress and let sit until slightly wilted, about 3 minutes. Season with salt, pepper, and extra soy sauce to taste. Serve.
Slow-Cooker Miso Soup With Shiitakes and Sweet Potatoes
Photography by Steve Klise. Styling by Catrine Kelty.

Slow-Cooker Miso Soup With Shiitakes and Sweet Potatoes

Headshot of Meaghen Walsh
By Meaghen Walsh
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Time

4 to 6 hours on low or 3 to 5 hours on high

Yield

Serves 6

Slow cooker size

4 to 7 quarts

Ingredients

12 ounces shiitake mushrooms, stemmed and sliced thin
2 scallions, sliced thin
1 (2-inch) piece ginger, peeled and sliced into ¼-inch-thick rounds
4 garlic cloves, minced
2 teaspoons toasted sesame oil
Salt and pepper
⅛ teaspoon red pepper flakes
6 cups water
½ cup white miso
14 ounces extra-firm tofu, cut into ½-inch cubes
12 ounces sweet potatoes, peeled and cut into ½-inch pieces
1 tablespoon soy sauce, plus extra for seasoning
3 ounces (3 cups) watercress, cut into 2-inch pieces

Ingredients

12 ounces shiitake mushrooms, stemmed and sliced thin
2 scallions, sliced thin
1 (2-inch) piece ginger, peeled and sliced into ¼-inch-thick rounds
4 garlic cloves, minced
2 teaspoons toasted sesame oil
Salt and pepper
⅛ teaspoon red pepper flakes
6 cups water
½ cup white miso
14 ounces extra-firm tofu, cut into ½-inch cubes
12 ounces sweet potatoes, peeled and cut into ½-inch pieces
1 tablespoon soy sauce, plus extra for seasoning
3 ounces (3 cups) watercress, cut into 2-inch pieces

Ingredients

12 ounces shiitake mushrooms, stemmed and sliced thin
2 scallions, sliced thin
1 (2-inch) piece ginger, peeled and sliced into ¼-inch-thick rounds
4 garlic cloves, minced
2 teaspoons toasted sesame oil
Salt and pepper
⅛ teaspoon red pepper flakes
6 cups water
½ cup white miso
14 ounces extra-firm tofu, cut into ½-inch cubes
12 ounces sweet potatoes, peeled and cut into ½-inch pieces
1 tablespoon soy sauce, plus extra for seasoning
3 ounces (3 cups) watercress, cut into 2-inch pieces

Why This Recipe Works

We started with water as the liquid base for our soup and infused it with a hearty amount of shiitake mushrooms, scallions, ginger, garlic, sesame oil, and red pepper flakes. We tried different types of miso, but tasters preferred the traditional white variety for its mild and slightly sweet flavor. Before adding the miso to the slow cooker, we found it best to thin the thick paste with a small amount of water to ensure that it would be fully incorporated into the soup. For extra protein we bumped up the amount of tofu, which is traditional in miso soup, and selected the extra-firm variety, as it held its shape best during cooking. For an interesting twist we added sweet potatoes for a little sweetness, and stirred in watercress for a fresh, peppery finish. 

Before You Begin

You can substitute firm tofu here if desired; avoid silken, soft, or medium-firm tofu, as these varieties will break down while cooking.

Instructions

  1. 1. Microwave mushrooms, scallions, ginger, garlic, oil, ¼ teaspoon salt, and pepper flakes in bowl, stirring occasionally, until mushrooms are softened, about 5 minutes; transfer to slow cooker.
  2. Whisk 1 cup water and miso in now-empty bowl until miso is fully dissolved. Stir miso mixture, tofu, potatoes, soy sauce, and remaining 5 cups water into slow cooker. Cover and cook until potatoes are tender, 4 to 6 hours on low or 3 to 5 hours on high.
  3. Discard ginger. Stir in watercress and let sit until slightly wilted, about 3 minutes. Season with salt, pepper, and extra soy sauce to taste. Serve.

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