Why You Shouldn’t Crush Sweet Leaf (Rau Ngót) While Washing It – and How to Cook the Perfect Sweet Leaf Soup

Many people are accustomed to crushing sweet leaf (rau ngót) during the washing process, thinking that it helps the leaves become cleaner and softer when cooked. In Vietnamese kitchens, this habit is extremely common.
However, nutrition expert Dr. Hoàng Thị Thúy Hà from the Clinical Nutrition Institute explains that this practice is not beneficial at all. Crushing the leaves before they are properly cleaned can cause the natural vitamins and minerals in sweet leaf to be washed away, resulting in a soup that is less nutritious and less flavorful.

Why You Shouldn’t Crush the Leaves While Washing

Sweet leaf contains a high amount of vitamin C, calcium, fiber, and other water-soluble nutrients. When you crush the leaves under running water, these nutrients can easily dissolve and get lost. Additionally, squeezing the leaves too early may cause them to turn darker and lose their natural sweetness during cooking.

If you want your sweet leaf to become tender more quickly when cooked, the correct method is:

• Wash the leaves thoroughly first to remove sand and dirt.

• After washing, gently crush or rub the leaves before placing them into boiling water.

• Do not crush the leaves too hard, and avoid rinsing them again after crushing.

This technique ensures that your soup remains vibrant, sweet, and full of nutrients while still achieving the soft texture you prefer.

How to Cook a Delicious and Nutritious Sweet Leaf Soup

Ingredients

• Sweet leaf (rau ngót): about 200g

• Broth: 1–1.5 liters (adjust to taste)

• Fresh shrimp: about 100g

  • You may replace shrimp with chicken or pork if preferred.

• Onion: 1 small bulb, thinly sliced

• Scallions: 1 stalk, finely chopped

• Tofu: 100g (optional)

• Seasonings: salt, pepper, cooking oil

Step-by-Step Instructions

1. Prepare the Sweet Leaf

• Rinse the leaves thoroughly under cold water to remove dust and grit.

• After they are clean, gently rub or crush the leaves so they soften and cook evenly.

• Avoid over-crushing, as this can bruise the leaves excessively.

2. Prepare the Broth

• Bring the broth to a boil.

• Add sliced onion and a portion of the scallions to infuse the stock with aroma.

• If you are using tofu, add it at this stage; tofu enhances sweetness and gives the soup a pleasant richness.

3. Cook the Protein

• When the broth returns to a full boil, add the shrimp.

  • If you use meat instead, season it lightly before cooking.

• Skim off any foam to keep the broth clear and appealing.

4. Add the Sweet Leaf

• Once the protein is fully cooked, add the prepared sweet leaf.

• Season with salt and pepper according to your taste.

• Cook for 2–3 minutes, just until the leaves soften. Overcooking may dull the color and flavor.

5. Finishing Touch

• Turn off the heat and add a small dash of cooking oil to make the soup glossy and fragrant.

• Ladle the soup into bowls and top with chopped scallions or a sprinkle of ground pepper.

Extra Tips for the Best Sweet Leaf Soup

✔ Crush the Leaves at the Right Time

Only crush the leaves after they’ve been washed, never during washing. This preserves nutrients and ensures a tender texture.

✔ Enhance the Flavor

You can add a spoonful of fried shallots or pounded shrimp paste for additional aroma, depending on the style of cooking you prefer.

✔ Maintain Bright Color

To keep the leaves bright green, avoid cooking them for too long. Adding them at the final stage helps preserve both color and sweetness.

✔ Customize Your Soup

Sweet leaf pairs well with shrimp, pork, minced chicken, tofu, or even mushroom for a vegetarian version. Each variation offers a slightly different flavor profile.