Is "ample" a proper adjective to modify a meal, in this case, lunch? So, can I say "an ample lunch?" What other words indicate that a meal was satisfying and plentiful? Also, what would be most commonly used term in the United States in this context (southern U.S. if possible)?
How do you want to use it? Do you want to advertise what will be provided? Do you want to comment on what you ate? Do you mean a lot of good food, or a lot of food, or almost-too-much food, or something else?

There are many possible words, but more context would help. For example you can say "A hearty lunch" but that implies the food itself was substantial. If there were tray after tray of little finger food items, that wouldn't apply very well, even though there was plenty of food, because little finger sandwiches wouldn't be considered "hearty."
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I'd like to describe a lunch that was both quick and plentiful (so, despite its quickness we had plenty to eat).
They quickly provided a tasty meal from which we could to eat our fill.
The provided a fast, tasty meal and we ate our fill.

The idea of "eating one's fill" seems appropriate to the desired speech pattern.
Make sense, thank you!
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