Coat potatoes with cooking spray and bake 45 to 60 minutes. Let rest until cool enough to touch.
Slice potatoes lengthwise in half and spoon out middles, leaving a shell.
Heat a cooking spray coated frying pan over medium heat. Cook onion, corn, bell pepper, and garlic 5 minutes.
Beat potato centers with sour cream and half the Cheddar cheese. Stir in vegetables and sprinkle with salt and pepper. Scoop mixture into potato shells and top with broccoli and the rest of the cheese.
Bake potatoes on a baking sheet at 350 degrees F for 20 to 30 minutes, until cheese is melted.