Preheat the oven to 500F.
Cut potatos in half lengthwise. (That is, let the spud lie on the table and cut parallel to the tabletop.) Core out the centers with a teaspoon. Leave about 1/4" of potato all around. Precision is not necessary. This also can be done in advance. Discard the centers or use them for mashed potatos or the like.
Melt the butter with the garlic. 45 seconds on high in a microwave is fine. Place the skins skin side up and paint a light coat of garlic butter on the skins. Turn them skin down and paint the other side. Place them on a foil-lined baking sheet and bake for about 20 minutes, until the edges start turning golden-brown. Leave the oven on.
While they are cooking, cook the bacon until crispy. Let cool and chop into bits.
Clean scallions and chop then separate the white parts.
Remove skins from oven and stuff with shredded cheese. A thick layer is sufficient. Precision is not necessary. Sprinkle bacon bits on skins. Return to the oven for about 5 minutes; the cheese should be cooked thoroughly, but not burnt.
Remove skins from oven and add a small dollop (to taste) of sour cream to each. Sprinkle chopped scallions on top.
Serves four as an appetizer or snack.
Jeff Goldsmith, firstname.lastname@example.org, June 3rd, 2001