Preheat the oven to 400 degrees F (204. C). Pierce each potato 3 to 4 times. Using a brush cover your potatoes with a layer of oil and place them on a large baking pan with raised edges. If you don’t have a raised baking pan line your pan with foil so it can catch the oil drippings. Sprinkle the outsides of the potatoes with sea salt and bake for 20 minutes. Take out and flip, and bake for an additional 20 minutes. Bake for longer if you are using large potatoes. Heat a pan on medium heat. Once hot, add the chopped broccoli and water. Cover pan with a lid and steam broccoli for 4-5 minutes or until the broccoli is tender. Heat a saucepan on medium heat. Once hot, add the butter and flour and whisk until a thick paste has been formed.Add the milk, cheddar cheese, garlic powder, and black pepper to the saucepan. Constantly whisk for 4-5 minutes until the cheese melts. Once the cheese melts turn the stove top on low. Make a medium slit on the top of the potato. Stuff it with the steamed broccoli and drizzle with the cheese sauce.