My friend Lillian came up with this recipe for the much-lamented Gourmet back in 2007, but I only just discovered it a few weeks ago, which means that there were seven long years that I missed out on this.
Poke desired number of white Japanese sweet potatoes with a fork and roast at 450F for 45 minutes to an hour. Meanwhile, allow half or a full stick (believe me, you’ll want to make as much of this as you can) of butter soften, then mash butter with a few scallions, chopped, and spoonful or two of miso paste. She says to use white miso, but red has worked just fine for me. Split roasted potatoes and liberally apply miso-scallion butter. I want to put this stuff on everything.