Pasta salad is a dish prepared with one or more types of pasta, usually chilled, and most often tossed in a vinegar, oil or mayonnaise-based dressing. It is typically served as an appetizer or a main course. The ingredients used vary widely by region, restaurant, seasonal availability, and/or preference of the preparer. The salad can be as simple as cold macaroni mixed with mayonnaise, or as elaborate as several pastas tossed together with a vinaigrette and a variety of fresh, preserved or cooked ingredients. These can include vegetables, legumes, cheeses, nuts, herbs, spices, meats, poultry, or seafood. Broccoli, carrots, baby corn, cucumbers, olives, onions, beans, chick peas, peppers, parmesan and feta cheeses are all popular ingredients in versions typically found at North American salad bars.