Slice or chop onions evenly
Heat a skillet over medium heat
Add a small amount of oil or butter
Add onions to the skillet in a single layer
Stir to coat onions with fat
Cook 5–10 minutes for softened onions, stirring occasionally
Cook 15–25 minutes for browned onions, stirring more frequently
Add a pinch of salt after 2–3 minutes to help draw out moisture
If onions brown too fast, lower heat and add a splash of water
Finish when onions are translucent and soft (or deeply golden for caramelized)
Remove from heat and use immediately