Crockpot Onion and Flanken Soup

A mint green crock filled with onion and flanken soup on a wood surface.

Who doesn’t love a big bowl of onion soup? However, making it can be time-consuming, as you have to sauté the onions for a long time while stirring them. This recipe allows you to skip the sautéing, as your crock pot does all the work for you.



12 onions sliced into half-moons
1 Tablespoon kosher salt
½ teaspoon freshly ground black pepper
¼ cup canola oil
2 pounds bone-in flanken
4 cups beef, chicken, or vegetable broth
¾ cup red wine
¼ cup red miso paste


1.    Combine onions, salt, pepper, and oil in a crockpot; stir to combine.
2.    Add flanken to the crockpot; cover with onion mixture. Cover; cook on high for 4-5 hours, until onions are golden brown.
3.    Add broth, wine, and miso paste; stir to combine. Cook on high for an additional hour.



Cook’s Tip
Miso paste is a paste made from fermented bean curd.  Used primarily in Japanese cooking, it adds umami, depth of flavor, to the dishes. Miso paste is available in a variety of colors; the darker the color, the stronger the flavor. I use them interchangeably.

Keywords: Perfect Flavors by Naomi Nachman, soup, onion soup, flanken, Crock pot