Scallion Pesto

Scallion pesto takes the typical herby spread and adds a burst of spring onion flavor to the mix. This pesto recipe is close to traditional pesto in style, using a handful of fresh ingredients to create a simple but flavorful no-cook sauce. It’s the perfect option for when you have extra green onions on hand or want to upgrade some basil pesto you already have on the shelf.

All it takes is a few scallions, basil, parsley, Parmesan cheese, pine nuts, and a few other simple accouterments to create a spread that can be used to dress up dinner on the fly or made ahead and used all throughout the week. With its bold flavor and blendable texture, scallion pesto can easily transform a typical everyday dish into a gourmet delicacy.  

History of Pesto

Originally from Genoa, Italy, pesto traces its name to the Italian word "pestare," which means "to crush or pound." For hundreds of years, pesto was made by pounding the ingredients in a mortar and pestle. Traditional pesto is made from fresh basil leaves, garlic, pine nuts, olive oil, and an aged hard cheese such as Parmigiano-Reggiano, and it's often tossed with pasta for a simply delicious dish.

While classic pesto is made by hand, this recipe uses a food processor or blender for a more modern technique.

Scallions vs. Green Onions vs. Spring Onions

Despite having various names, the long, green-topped onions are one in the same. The terms “scallion” and “green onion” refer to the plant’s age. Scallions are young green onions, you can tell them apart by the width of the white bulb at its base, a scallion’s white bulb will be slimmer than a green onions.

Spring onions are older than scallions and green onions, they are slightly stronger in flavor and can be identified by its rounded white bulb.

Both the leaves and bulbs of these onions are edible and have a mild, gentle flavor compared to regular onions. Though there are slight differences between scallions, green onions, and spring onions, they can be used interchangeably in this recipe.

How to Keep Your Pesto Green

Part of what makes pesto so appealing is its vibrant bright green hue. However, after a while (like guacamole), oxidation can cause your pesto to turn brown. To keep your scallion pesto colorful, blanch the basil and parsley for 1-2 minutes in boiling water, and then shock the herbs in an ice water bath. The boiling water kills the browning enzymes that quickly cause the leaves—and the resulting pesto—to turn dark. Also, adding a bit of acid like lemon juice to your pesto when you mix it can help preserve the color of your sauce.

To keep the pesto from changing color during storage, place the pesto in a container and pour a thin layer of oil over the top to prevent the air from getting to the pesto.

How to Use Scallion Pesto

From breakfast to dinner, scallion pesto is a versatile sauce that is easily enjoyed in or on many different dishes. The addition of green onion to this pesto makes it the perfect herby topping for a grilled steak, an easy way to elevate your morning eggs, or a simple spread that adds an oniony twist to toasted bread.

Try it with some of these recipes:

• Angel Hair Pasta With Garlic, Herbs, and Parmesan
• Bruschetta With Tomato and Basil
• How to Make an Omelette
• Grilled Chili Lime Flank Steak
• Rosemary Focaccia

Scallion Pesto Swaps and Substitutions

Since pesto is such a flexible spread to create, you can easily adjust the ingredients based on what you have on hand or to fit your taste.

• Unlike the traditional pesto, this recipe doesn’t call for garlic however feel free to add a clove or two for an extra kick.
• If you find the onion flavor is too overpowering, try swapping half of the basil for fresh baby spinach to mellow out the flavor.
• To get the same texture with little to no onion flavor, replace the scallions with leeks.
• For a slightly more robust flavor, use a hard cheese such as Pecorino Romano, or Pecorino Sardo.
• When it comes to nuts, toasted almonds would work great in place of the pricier pine nuts in this recipe.

How to Store Pesto

Pesto is the perfect make-ahead spread, and it stores and freezes like a dream. 
Fresh scallion pesto can be stored in an airtight container with a layer of oil on top in the refrigerator for up to 1 week. Once you’re ready to use, just stir in the oil to bring your pesto back to life.

To freeze, line an ice cube tray with plastic wrap and add a spoonful of pesto to each cube. Freeze and then remove from the ice tray and store in a freezer-safe, zip-top bag for convenient single-serve pesto portions. The pesto will keep in the freezer for up to 12 months.

More Pesto Recipes to Try

One of the best things about pesto is it can be adapted to work with almost any leafy green, fresh herb, and nut combination you please. It’s the perfect way to use extra herbs or wilting greens and makes a great no-waste recipe for uncommonly used vegetables like carrot tops or beet leaves. You can also use cashews, pistachios, almonds, sunflower seeds or, even pumpkin seeds (but make sure they have the hulls removed). 

From mint to kale, here are some delicious ways to spice up your traditional pesto recipe:

• Mint Pesto
• Carrot Top Pesto
• Arugula Pesto
• Sun-Dried Tomato Pesto
• Cilantro Pesto
• Kale Pesto