The standard way to slice an onion for frying is into half-moons. This shape cooks evenly and provides a good surface area for browning.
When preparing onions for frying, the goal is to achieve even cooking and browning. Half-moons are ideal because they offer a balance between surface area and thickness. Here's a step-by-step guide:
Peel the Onion: Remove the outer papery skin of the onion.
Cut in Half: Slice the onion in half from the stem end to the root end.
Place Flat Side Down: Place one half of the onion flat-side down on your cutting board.
Slice into Half-Moons: Starting at one edge, slice the onion into even, crescent-shaped pieces, following the natural curve of the onion. Aim for a thickness of about 1/4 inch (6mm) for optimal cooking.
Repeat: Repeat the process with the other half of the onion.
While rings can be used, they often cook unevenly, with the thinner parts burning before the thicker parts are cooked through. Dicing is more suitable for sauces and stews where the onion is meant to dissolve.
To avoid excessive tearing while slicing onions, chill them in the refrigerator for about 30 minutes before cutting. This slows down the release of the irritating compounds that cause your eyes to water.