How can I gain 10 pounds quickly?

I'm a bit more underweight than I would like to me, male, 5'7", 115-120 lbs. Would like to be at least 130lbs. But I want to do it healthily. I'm not looking to build mucho muscle (too much work), I can tone up pretty easily, but what should I be eating to gain this wait quickly and permanently? I know I could gobble Micky D's all day every day and fatten up pretty quick but I won't be doing a favor to my health. So what sorts of food should I be eating?