There's only one solution to this. Eat. Yes, stuff your face. Drinking milk for breakfast? Wrong! Drink cream. Eating a burger? Slop on the mayo and cheese! It's not very healthy, and usually rapid weight gain/loss is not. If you really want it though, stop reading this and chove your face in some food
Every pound = 3600 calories. So you need and extra 36000 calories on top of what you already eat, capiche?