Sharpening a Knife and Chopping Onions

Learn How to Sharpen a Knife and Chop Onions

Master your knife skills and make preparing food easy with our Cookery School video showing you how to sharpen a knife properly, how to chop onions and preparing Delia's recipe for Grilled Spanish Onion Salad - simple and easy to make.

Start with the Basics: Sharpening Your Knife

Before you even pick up an onion, the key to safe and easy chopping is having a super sharp knife. A good cook’s knife is essential in every kitchen—ideally, one with a bit of flexibility. Alongside that, you’ll want a sharpening steel, a timeless tool that, if used properly, can last a lifetime.

How to Sharpen a Knife

To get started, hold your sharpening steel horizontally in front of you. Then, using the heel of the knife (that’s the part closest to the handle), gently slide the blade down at an angle until you reach the tip. Repeat on the other side of the steel. Do this a few times - slowly at first - then gradually pick up speed as you get comfortable.

Once you’ve got the technique, adjust the angle if you need to. The golden rule for knife maintenance is sharpen little and often. It keeps your blade in top condition and makes food preparation so much easier (and safer!).

Ready to chop?

Now that your knife is razor-sharp, you’re ready to slice into those onions. Watch the full video to see the technique in action and follow along with Delia's Grilled Spanish Onion Salad, a recipe that brings out the natural sweetness of grilled onions.

Delia's essential knife advice

For a well-equipped kitchen, Delia recommends lightweight, flexible cook’s knives in a range of sizes, a serrated palette knife for multitasking, a curved paring knife for peeling, sturdy kitchen scissors, and proper care, including storing knives safely, using forgiving cutting boards.