How to Dice an Onion

Dicing an onion is a fundamental cooking skill. Follow these simple steps for perfectly diced onions every time.

Preparing the Onion

Cut in Half: First, cut the onion in half from the stem to the root, leaving the root intact. This helps hold the onion together during the dicing process. (Reference: Multiple sources including SimplyRecipes, The Spruce Eats, and Reddit discussions)
Peel (Optional): Remove the outer layers of the onion if desired. This step is optional; many cooks leave the outer layer on until after dicing for better grip.

Vertical Slices: Place one onion half, flat side down, on your cutting board. Make several vertical slices, stopping just short of the root end. Aim for 2-3 slices depending on the desired dice size. (Reference: Reddit threads and various YouTube tutorials)
Horizontal Slices: Rotate the onion half so the vertical slices are now facing upwards. Make several horizontal slices, again stopping just short of the root end, creating a diced pattern. (Reference: Paula Deen's YouTube video and many other tutorials)
Finishing Cuts: Using your knife, carefully cut through the onion from the root end creating uniform diced pieces. (Reference: Gordon Ramsay's YouTube video and various instructional websites)

Sharp Knife: Use a sharp knife for clean cuts and to prevent bruising the onion.
Claw Grip: Use the claw grip (curling your fingertips inward) to keep your fingers safe while slicing.
Onion Root: Keep the root end intact until the final cuts to prevent the onion from falling apart.

The size of your dice can be adjusted by altering the spacing and number of your vertical and horizontal slices.