Everyone should know how to cut onions these 3 ways. I'll show you how to slice an onion into strips perfect for sausage and peppers, a dice perfect for soups and most recipes and then a small dice for a more refined cut. Practice this every time you cook and you will be amazed at how much faster the process becomes. Chopping an onion is the first step to becoming a master in the kitchen. This is 3 WAYS TO CUT AN ONION.