Vermouth is a fortified wine that is used in many cocktails as a standard ingredient. While there are both “sweet” and “dry” varieties, a sweet vermouth isn’t going to taste like grenadine. Where a dry vermouth has a herbaceous flavor, sweet vermouth has a spicy, earthy taste. As you know from our post on making a Manhattan, a traditional Manhattan typically uses sweet vermouth. You can make a drier drink by switching to dry instead. There’s also lots of ways to spice up cocktails like the “Vermouth cocktail” or “Carpano-rita” with sweet vermouth.
You can even try it straight, maybe adding a twist of lemon or orange–citrus brightens the flavor. People might look at you funny at a party when you pour vermouth into a glass, but you can always just tell them that Europeans do this all the time. Since vermouth comes from Italy (producers of the sweet) and France (producers of the dry), I think they know what they’re doing.