03Put remaining oil in a skillet that can be covered and is large enough to accommodate cabbage rolls; turn heat to medium-high. Add onion, and stir occasionally, until it softens, 3 to 5 minutes. Add tomatoes and some salt and pepper, and stir occasionally until tomatoes break up, 5 to 10 minutes. Add cabbage rolls, and cover, adjusting the heat so the mixture simmers.04Cook 10 to 15 minutes, turning once, until rolls are firm; taste sauce to adjust seasoning. Serve with some sauce spooned over and garnished with parsley.