Nothing cuts the mustard like moutarde violette, an opulent condiment with a deep violet hue from the Limousin region of south central France: It marries the spicy pop of whole black mustard seeds with the molasses-like sweetness of reduced grape must (the juice of just-pressed wine grapes). Clove-scented with a mouthwatering tang, the mustard enhances sauces and vinaigrettes, brings a sweet counterpoint to aged cheddar cheese, and shines on baked ham and smoked turkey. But I also enjoy it as they do in Limousin, dabbed onto boiled beef on a slice of steamed bread.