Preheat your oven to 400°F (200°C).
Wash and poke holes in each potato.
Bake the potatoes for about 45 minutes.
While potatoes are baking, steam the broccoli florets until tender.
Remove potatoes from the oven and let them cool slightly.
Cut each potato in half lengthwise and scoop out the insides.
In a mixing bowl, combine the scooped potato, broccoli, cheddar cheese, sour cream, milk, butter, salt, pepper, and garlic powder until well blended.
Refill each potato half with the broccoli cheddar mixture.
Sprinkle the tops with extra cheese if desired.
Return the stuffed potatoes to the oven and bake for 15 to 20 minutes.
Serve immediately, garnished with chives or green onions if desired.