If you’ve ever followed a recipe for green bean casserole or stir fry that calls for fresh green beans, chances are you’ve come across the term blanching. But what exactly is blanching, and why is it used for cooking green beans? For more information and a step-by-step how-to, we consulted Khailing Neoh, owner of Sum Bar in Greenville, SC.

What Is Blanching?

Blanching is a process of briefly cooking vegetables in boiling salted water and then shocking them in an ice bath to halt the cooking process.

“The basics of blanching involve briefly immersing vegetables, fruit or nuts in hot liquid such as water/steam, stock or oil anywhere from 30 seconds to a few minutes,” Neoh says. “It's often followed with shocking—plunging the blanched items directly into an ice water bath to stop them from cooking further. Think of shocking as a superpower to choose the exact amount of doneness.”

Why Would You Blanch Green Beans?

Blanching green beans can preserve flavor, color and texture for use in green bean casseroles, salads, crudité platters and stir fries. “You can keep the texture crisp and fresh-tasting while showcasing the vibrant colors of the produce," Neoh says. "Other positives are loosening the skin to make peeling easier and to help preserve nutrients."

"Blanching is a great precursor to stir frying," she adds. "It prevents vegetables from turning brown/gray and mushy and helps them cook more evenly.”

How to Blanch Green Beans, Step-By-Step

For Casseroles, Salads and Crudité

Step 1: Prepare the green beans. Wash and trim the green beans. If you like smaller pieces in your casserole feel free to cut them in half or shorter.

Step 2: Prepare an ice bath. Prepare a large ice bath by filling a large bowl with water and ice.

Step 3: Cook the green beans. Bring a pot of salted water to a boil and cook the green beans until crisp-tender: 5-7 minutes for salads, about 3-5 min for casseroles or crudité. “Cook in batches depending on the amount of green beans,” Noeh says. “Overcrowding the pot will lower the temperature of the boiling water which affects the outcome of the blanch.”

Step 4: Shock the green beans. Use a slotted spoon to gather the green beans and shock in ice bath for a couple minutes until cooled.

Step 5: Dry the green beans. Set green beans aside on a cloth or paper towel to dry. Use as desired.

For Classic Chinese-Style Green Beans

Step 1: Prepare the green beans. Wash and trim the green beans.

Step 2: Prepare an ice bath. Prepare a large ice bath by filling a large bowl with water and ice.

Step 3: Cook the green beans. Bring a pot of salted water to a boil and blanch the green beans for about 2 minutes. Neoh shares that one trick in Chinese cooking is to add 1 to 2 teaspoons of neutral cooking oil to the boiling water pot before blanching, which is said to enhance flavor and color. “I can't find a good source that explains why or if it's noticeably effective,” she says. “It's one of those cultural things that some people do but can't tell you why.”

Step 4: Shock the green beans. Shock the green beans in an ice bath to cool down, then pat dry.

Step 5: Fry the green beans. Heat a deep pan or wok over high heat and add about 3 Tablespoons of oil to fry the green beans. Test out a green bean by gently dropping in oil; it should sizzle and bubble if the oil is hot enough. Fry green beans for about a minute or until they're evenly wrinkly. (Optional: add garlic and/or chili oil to the oil before frying the green beans.)

Step 6: Add sauce and garnish. Add any prepared sauce you'd like to the green beans, either in the pan or in a clean bowl. Some favorite combinations are oyster sauce, soy, sugar and chicken bouillon. Finish the green beans off with a bit of sesame oil and sesame seeds.

How Long to Blanch Green Beans

The length of time required to blanch green beans depends on the intended use. Neoh recommends blanching green beans 5 to 7 minutes for salads, 3 to 5 minutes for casseroles or crudité and 1 to 2 minutes for stir fries. For more info, check out our primer How To Cook Green Beans.

Related Links:

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