I will show you how to caramelize onions to sweet and golden perfection with this step by step tutorial.
Cut off the stem ends, and roll the onion so that one cut side lays flat on the board.
Cut the onion in half, from one stem end to the other, and peel of dry outer skins.
Place a half, flat side down, on the board, and cut into strips from one stem-end to the other. Repeat for the other half.
Melt some butter over medium heat in a pan, and place your strips into the melted butter, using your hands to start to separate out the strips.
Give everything a good stir to coat all the pieces in butter. Once it is sizzling, reduce heat to LOW.
Then leave them alone (without stirring) for about 5 minutes until some little golden edges start to show up.
Give them a good stir, and let them go 20 to 25 minutes more, stirring about every 5 minutes.
Add about 1/4 cup water (or stock - vegetable or chicken works best) to deglaze the pan, and use a wooden spoon to scrape up all those brown bits.
Cook until the liquid reduces, about another 3 to 5 minutes. (Optional 2nd splash of liquid: Add 2 Tablespoons more liquid, if you want them to get a little more done or if you need to pick up more brown bits off the bottom, and reduce again.)
Salt and pepper to taste.
Serve on salads, burgers, steaks, chicken, pastas, etc.
I have caramelized up to three onions in my 12 inch pan (Amazon affiliate) at once. It may be a little crowded at first, but it still works. It may add a little additional cook time too, FYI.
Never add salt and pepper until the very end! Adding salt too early will release water from the onion and mess with the caramelization process.
You can refrigerate these up to a week and freeze them up to 3 months.
I like my onions sliced into strips, as shown above. You could also dice them or slice them into rings. I prefer the strips, though, because everything seems to cook more consistently for me in this shape.
Optional: you can add a pinch of white sugar a few minutes into cooking if you wish. I did NOT use sugar for mine, FYI. This may be helpful if you are using a less sweet variety, such as white onion.