Canh Khoai Mo / Purple Yam Soup

Vietnamese cuisine is full of comforting soups that rarely ever make it onto restaurant menus. These homestyle dishes are the heart of Vietnamese family meals, also known as com gia dinh. They’re simple, nourishing, and built on generations of tradition. Canh Khoai Mo or Purple Yam Soup is one of those soups. It’s gentle and creamy with a soft earthiness that reminds me of what it feels like to be cooked for by someone who loves you. If you grew up eating Vietnamese food, you know that soups like this show up year-round. They are light enough for hot weather yet cozy enough for cold days. Every family makes its own version, but the dish’s soul is always the same!

What Is Canh Khoai Mo

Canh khoai mo is a traditional Vietnamese soup made from purple yams. It’s known for its naturally lavender color and creamy, velvety texture. This soup is especially popular in Central Vietnam, where root vegetables thrive and where many classic canh recipes originate. It is simple peasant-style cooking done right, transforming a few humble ingredients into something both nourishing and beautiful. People love this soup because it is light yet filling. The yam thickens the broth naturally, giving it a soft consistency without the need for cream or starch. It is usually paired with ground pork or dried shrimp, and for my recipe today, we’re using ground pork.

What Is Khoai Mo

Khoai mo is the star of this recipe. It goes by several names depending on where you are. Purple yam, ube, water yam, and Dioscorea alata are some of the most common. In Vietnam, khoai mo refers explicitly to the yam with pale lavender flesh that becomes creamy when cooked. It’s not to be confused with taro, even though they share some similarities. Taro typically has white flesh with speckles and a more fibrous texture, while khoai mo has a smooth interior that ranges from light lilac to deep violet. The skin is thin and brown with a slightly flaky exterior.

The flavor of khoai mo is mildly sweet and earthy. When simmered in broth, it softens into a velvety mash that naturally thickens the soup. This is what gives canh khoai mo its signature texture. It feels almost like a light chowder but remains unmistakably Vietnamese. If you can’t find this root fresh, most Vietnamese or Southeast Asian grocery stores will carry it prepped in the freezer section.

How to Make Canh Khoai Mo

Making Canh Khoai Mo is surprisingly easy. This is the kind of recipe that rewards patience and simple technique rather than complexity. The core steps remain the same whether your family uses pork, dried shrimp, or keeps it vegetarian.

Prep the ingredients:

Before cooking, spend a little bit of time getting all your mise en place ready. Start by finely dicing a small shallot and a few garlic cloves. Then peel the purple yams. Using a metal spoon or a grater, finely grate the purple yam until it turns into a mash.

For the herbs, we’re using culantro and rice paddy herbs. Roughly chop both and set aside.

Cook the soup:

In a pot, sauté minced shallots and garlic until aromatic. Add ground pork, using a wooden spatula to break up any large clumps, and then season with salt. Pour in 2 quarts of water, bring it up to a boil, and skim off any impurities that rise to the top.

Add in the grated purple yams, and then season with sugar and MSG. Reduce the heat to low and let the soup simmer, covered with a slight crack, for 25-30 minutes. Skim off any impurities as necessary, and season to taste with fish sauce. Turn off the heat, and add in culantro and rice paddy herbs. Mix well and serve.

Serve:

Like most Vietnamese soups, Canh Khoai Mo is meant to be enjoyed alongside a full family meal. Pair it with a protein, pickled vegetables, and hot rice for the complete com gia dinh experience.