Without a commonly-used term to say, "Enjoy your meal," as found in French (Bon appétit) and Spanish (provecho), English did what it does best: importation.

"Bon appétit" is now used quite commonly by English-speakers to wish someone a good meal.

Compare with other importations Gesundheit, bon voyage.

The Bon Appétit Management Company, referred to simply as "Bon Appétit" for short, is a catering company serving colleges and offices that prides itself on "onsite custom restaurants". While it claims that there is nothing cafeteria-like about their "restaurants", my experiences with their food at Macalester College and Lewis and Clark College would tend to contradict that. Bon Appétit is based out of Palo Alto, CA.