Peel your onions and slice them thinly. Consistent slices are key for even cooking. About ¼ inch thick works best.
Use a large, wide skillet or sauté pan. Add butter, olive oil, or a mix of both over medium heat. The fat prevents sticking and gives the onions that luxurious flavor.
Toss in the sliced onions, spreading them out evenly. Sprinkle with a pinch of salt to help them release their moisture.
Reduce the heat to medium-low and stir every 5–10 minutes. Caramelization takes time—usually 30–45 minutes. Resist the urge to rush. The onions will first soften, then turn translucent, and finally develop that deep golden-brown color.
Deglaze the Pan (Optional)
If the onions stick, add a splash of water, broth, or wine to deglaze the pan. This lifts the browned bits and intensifies flavor.
Finish and Store
Once caramelized, remove from heat. Use immediately or let cool and store in an airtight container in the fridge for up to 5 days. They also freeze beautifully—portion into small bags or containers for easy use later.