Preheat the oven to 425 degrees F and line a large, rimmed baking sheet with foil.
Combine the miso, butter, honey, vinegar, crushed red pepper, and black pepper in a large bowl. Mash the mixture with a fork until it’s well combined.
Add the chicken to the bowl and massage the miso mixture all over it. (For best flavor, I like to work some of it under the skin, too.) Place the chicken in a single layer, skin side down, on the prepared baking sheet. Bake for 30-35 minutes, depending upon the size of the chicken pieces, turning the pieces skin-side up after the first 15 minutes. The internal temperature of the meat should register 160-165 degrees on a quick-read thermometer. If desired, broil the chicken for a minute or two, watching very closely, to further brown and crisp the skin.
For less fat or if you’re simply not a fan, you can peel off the skin before coating with the miso mixture—or do half and half if some like skin and others don’t.
For the ideal miso-to-chicken ratio, use the specified chicken weight as a guideline when buying. For example, if the chicken thighs are small, you’ll have enough miso mixture to coat a higher number of thighs.
The recipe can easily be cut in half, but leftovers are rather tasty.