Heat the oven to 425F. Scrub and dry the sweet potatoes, then prick each one four or five times with a fork.

Rub the potatoes with olive oil and kosher salt and set them directly on a rimmed baking sheet. Do not wrap them in foil.

Bake 45 to 55 minutes, until a knife slides into the thickest part with no resistance and the skins look slightly wrinkled.

Pull the cooked chicken into rough, ragged shreds. If it is cold, warm it in a skillet over low heat for 2 minutes.

Melt the butter in a small saucepan over medium-low heat until just liquid, then take the pan off the heat.

Whisk the hot sauce into the melted butter a splash at a time, letting each addition go smooth and glossy before adding the next. Whisk in the vinegar, Worcestershire, garlic powder, and smoked paprika.

Pour the sauce over the warm chicken and fold it through. Let it rest 2 to 3 minutes so the shreds absorb the sauce.

Stir the sour cream, crumbled blue cheese, milk, lemon juice, and black pepper together in a small bowl, leaving some crumbles whole. Add another splash of milk if it is too thick to pour.

Split each hot potato lengthwise, cutting about three quarters of the way through. Press the ends toward each other so the flesh opens up.

Fluff the flesh with a fork and season it with a small pinch of salt.

Pile the buffalo chicken into the opening, spoon the blue cheese sauce over the top, and finish with sliced green onions and celery. Serve hot.