Scrub the potato and prick several time with the tines of a fork. Place on a plate.
Cook on full power in the microwave for 5 minutes. Turn over and continue to cook for 5 more minutes.
When the potato is soft remove from the microwave and cut in half lengthwise. Season with salt and pepper then mash up the inside a little using a fork. Top the open sides with butter and 2 tablespoons of cheese.
Return to the microwave and cook for about 1 minute to melt the cheese.
Top with remaining cheese and sour cream, and serve.