Rinse the chicken livers and pat them dry
Trim away any fat, connective tissue, or green spots
Season with salt and pepper
Heat oil or butter in a skillet over medium heat
Add sliced onions or garlic if desired
Cook the livers in a single layer
Sear for 2 to 3 minutes per side
Cook until browned outside and just cooked through inside
Avoid overcooking
Remove from the pan and serve immediately
Serve with rice, bread, mashed potatoes, or vegetables