Harissa, the zesty Tunisian sauce typically made with chiles, garlic, cumin, coriander, caraway and olive oil, is not just for couscous anymore. Chefs of all ethnic backgrounds at restaurants of all kinds are increasingly serving it with everything from seafood to cheese, and even in chicken wraps.According to recent research from Datassential MenuTrends, a slew of Mediterranean ingredients have begun showing up on more menus in recent years. Harissa is among the fastest growing Mediterranean ingredients, appearing on 78 percent more menus than just four years ago. “I love harissa because it’s so versatile, you can use it as a condiment,