Ingredients

2 tablespoons unsalted butter 

3 medium to large red onions, sliced 1/4 inch thick 

1 teaspoon sugar 

Coarse salt and freshly ground pepper 

Preparation

Heat butter in a large skillet over medium heat. Add onions, and sprinkle with sugar. Cook, stirring frequently, until soft and golden brown, about 1 hour, reducing heat to medium-low about halfway through. If onions begin to stick to skillet, add 1 to 2 tablespoons water. Remove from heat, and season with salt and pepper. Let cool before using.