The most common and most likely answer to this crossword clue is the 7 letter word SCOFFER
I've seen this crossword clue in The Guardian
S
C
O
F
F
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R
More clues leading to the result SCOFFER
- One who mocks a greedy eater?
- One who'll eat and drink, briefly entertained by sister
- One who’s likely to ridicule small chest
- One who mocks someone who eats greedily
- I doubt he eats very quickly
- Empty samovar to hold endless drink one guzzles
- Son gets box — one greedy for chocolates, maybe?
- Person making a mockery of a gourmand?
- One teases, initially showing chest
Buddy explains!

The straight part
We know that "One teases" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case one teases = scoffer.The cryptic/wordplay part
In cryptic crossword there's often an wordplay/cryptic part as well.This part involves a more complex hint, such as an anagram, homophone, hidden word, etc.
Sadly, We don't have an explanation for this specific crossword clue yet.