Pierce each potato 3 to 4 times with a fork, and place directly on oven rack.
Bake at 450° for 1 hour and 30 minutes. Let cool slightly, about 15 minutes.
Cut bell peppers in half lengthwise, cutting through stems and keeping intact. Remove and discard seeds and membranes; rinse and pat dry. Set aside.
Cut baked potatoes in half. Scoop out pulp into a large bowl, discarding shells. Add sour cream and next 6 ingredients to pulp, blending well with a fork or potato masher.
Spoon potato mixture evenly into bell pepper halves. Sprinkle with paprika.
Grill peppers, covered with grill lid, over medium-high heat (350° to 400°) 18 minutes or until peppers are blistered and potato mixture bubbles around edges. Serve immediately.
Note: We tried microwaving the potatoes, but the texture is mealy; baking is the best choice.
Grilled Stuffed Potatoes: Omit red bell peppers. Proceed with recipe as directed, reserving potato shells and spooning potato mixture into reserved potato shells. Grill as directed or bake at 350° for 20 minutes or until thoroughly heated.