Poke several holes in the sweet potato with a fork or knife.
Cook the potato in the microwave for 6 -7 minutes on high, until done.
In a small skillet or saucepan coated with cooking spray, cook onions and ham with lid on for about 3 minutes, then remove lid and cook until onions are softened and slightly browned.
Split open the sweet potato and top with onion, ham, salt, pepper and butter to taste. De-e-elish!