Pierce potatoes all over with a fork. Place in the microwave and cook on Medium, turning once or twice, until the potatoes are soft, about 20 minutes.
Meanwhile, brown meat in a large skillet over medium-high heat, stirring often, about 3 minutes. Transfer to a large bowl. Increase heat to high, add broccoli and water to the pan, cover, and cook until tender, 4 to 5 minutes. Drain the broccoli; add to the meat.
Carefully cut off the top third of the cooked potatoes; reserve the tops for another use. Scoop out the insides into a medium bowl. Place the potato shells in a small baking dish. Add 1/2 cup Cheddar, sour cream, salt and pepper to the potato insides and mash with a fork or potato masher. Add scallions and the potato mixture to the broccoli and meat; stir to combine.
Evenly divide the potato mixture among the potato shells and top with the remaining 1/2 cup cheese. Microwave on High until the filling is hot and the cheese is melted, 2 to 4 minutes.
Makes 4 Servings (1 Potato Per Serving)
Nutritional Info Per Serving: 274 calories; 10 g fat; 52 mg cholesterol; 24 g carbohydrates;
22 g protein; 2 g fiber; 514 mg sodium