To Slice the Onions

Cup of Yum
1. Halve each onion lengthwise (root end to tip). Cut the root out of each half by trimming a "v" shape around the solid white area. Remove and discard the onion peels. 
2. Slice the onion halves lengthwise into 1/4-inch thick wedges. The angle of your knife should follow the curve of the onion slice. Separate the layers.
3. You can also slice the onions into a half moon shape. Cut the onions in half lengthwise, and then slice them crosswise into 1/4-inch thick slices. Make sure your onions are sliced as uniformly as possible so they caramelize evenly.

To Caramelize

1. Melt butter and oil over medium-high heat until foaming subsides. Add onions and a pinch of kosher salt and cook until onions begin to soften and release their liquid, about 5 minutes.
2. Lower heat and cook, stirring often, until onions are soft and golden brown, about 30-40 minutes longer. Deglaze the pan with 1 tablespoon of your liquid of choice and cook, stirring, for an additional 1-2 minutes, scraping any brown bits from the bottom of the pan.
3. Use, as directed, in your recipe. Caramelized onions can be stored, tightly covered, in the refrigerator for 3-4 days, and in the freezer for up to 3 months. (Click here to read about additional storage instructions.)