4 Japanese or Garnet sweet potatoes
3/4 sticks unsalted butter, well softened
1 tablespoons miso paste (preferably white)
1 1/2 tablespoons finely chopped scallion
1) Preheat oven to 450°F with rack in upper third.
2) Prick potatoes all over with a fork and put on a foil-lined large baking sheet. Bake until very soft when squeezed, 45 minutes to 1 hour.
3) While potatoes bake, stir together butter, miso, and scallion until combined.
4) Slit hot potatoes lengthwise and, using oven mitts, push in sides to puff up potato. 5) Serve with some scallion butter in center of each and with additional scallion butter on the side.