What food service style is best for a casual gathering where guests arrive and leave at various times?

The buffet style is the best choice for a casual gathering where guests arrive and leave at various times because it allows for flexibility and convenience. In a buffet setup, a variety of food options are displayed on a table or counter, and guests can serve themselves at their own pace. This setup accommodates individuals arriving at different times, as guests can simply help themselves to food whenever they choose without the need for formal serving or seating arrangements.

Additionally, a buffet encourages social interaction as guests can mingle while selecting their food, making it ideal for a relaxed environment. This style also reduces the need for coordination by hosts since guests are responsible for serving themselves. It's a practical solution that fits the dynamics of a casual event where the flow of guests is unpredictable.

Other food service styles might not provide the same ease of access or flexibility required for such an informal setting. For instance, blue plate service typically involves meals served directly to guests at set times, family style requires passing dishes around the table, and continental breakfasts are usually more structured and limited in scope.