Caramelized Onions

In a large, heavy-bottomed skillet, melt the butter with the oil over medium-high heat. Add the onions, salt, pepper, and sugar. Cook, uncovered, stirring frequently with a wooden spoon, until the onions are slightly softened, 4 to 5 minutes.

Reduce the heat to medium and continue cooking, uncovered and stirring occasionally, until the onions are a rich golden brown color. This process can take anywhere from 45 to 75 minutes. In the beginning, you will only need to stir the onions occasionally. However, as the onions cook down and begin to brown, you will need to stir them more frequently, scraping the fond (the brown particles) from the bottom of the pan. Towards the end of the caramelization process, the fond will start to stick to the pan, so you will need to occasionally deglaze the pan with a few tablespoons of water, scraping up the fond with a wooden spoon, to prevent burning and promote even caramelization. Repeat the deglazing process with the water as needed until caramelization is achieved. Once the onions have achieved the rich golden brown color, remove them from the skillet, let cool, and store in a covered container in the refrigerator.