Welcome to Melvin's Kitchen. But don't let your appetite lead you astray - go left, let your fellows kill the sheepies and break stuff. Enter the main room, turn the wheel you see across (#1) to roast the butcher cooks. Take a walk around the room, clear the area and turn another wheel (#2). Enter the room and clean it up. Now get ready for meeting Melvin Underbelly himself... Brrr.
Start from a distance - use your minions (#1), fireball, hit him with your axe from behind. Now you see he started rolling all over the room! - be careful not to get in the range of this floppy belly (it's wider than it seems!). Make sure your minions follow you as you call them and be careful not to get crashed or hit by the stick in Melvin's hand. It will take some time so be patient. The best moment to attack is when he stands by the wall (#2). After a few hits the fatass will explode - but literally.