Preheat oven to 350 degrees F (175 degrees C).
Clean and scrub potatoes.
Pierce skin with a fork once or twice and bake for approximately 1 hour or until potatoes are soft and firm.
Let potatoes cool slightly. Cut baked potatoes in half and scoop out pulp within 1/4 inch of shell edge. Mash pulp with milk, salt, and butter to taste.
Stuff shells with mashed pulp mixture and sprinkle tops with shredded cheddar cheese.
Place potatoes on a baking sheet and bake at 350 degrees F (175 degrees C) for 15 minutes or until cheese is melted and bubbly.