Step 1

Heat oil or butter in large skillet over medium heat. Add onions and cook, stirring occasionally, until softened and translucent, about 10 minutes.

Step 2

Reduce heat to low and season with salt and pepper.

Step 3

Continue cooking, stirring occasionally, for about 30-45 minutes, or until the onions are deeply golden brown and very soft. If onions start to burn quickly or start sticking to pan, add more oil or butter.

Step 4

If desired, add a splash of balsamic vinegar to deglaze the pan.

Step 5

Taste and adjust seasonings as needed. Serve warm or at room temperature.