Rich, tangy buttermilk lends a savory note to the candied-like flavor of roasted sweet potatoes.
Preheat oven to 425 degrees. Toss wedges with olive oil and season with salt; roast until tender, about 20 minutes. For the dip, whisk together buttermilk, mayonnaise and dill; season with salt. Sprinkle with more dill before serving.