Similar to a shrub—a fruit syrup punctuated by vinegar—this blueberry sauce makes a bracing drink when mixed with club soda or booze. It's also the first step in a fruity vinaigrette and is a perfect glaze on oven-baked chicken. Keep in mind this is not a marinade. Brush it on toward the end of cooking and let the chicken soak up more of the sauce before serving. The final soak is key.