The most common and most likely answer to this crossword clue is the 5 plus 2 plus 3 plus 3 letter word FLASH IN THE PAN
I've seen this crossword clue in The Daily Telegraph
F
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A
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P
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More clues leading to the result FLASH IN THE PAN
- Baked dish containing cut of beef and hard pate mixture is only a very brief hit
- Ray and I then repaired toilet – a brief success
- Infant has help running project enjoying fleeting success
- Brief success for chef?
- Brief success, cook’s brilliant moment?
- Ephemeral success that’s seen with a crepe suzette?
- Cleaner around toilet having brief success
- Arrange help, infant has not repeated earlier success
- Light and fashionable, the cooking vessel is an instant hit
- Panic about sport largely linked to explosive article? It has short-lived impact
Buddy explains!
The straight part
We know that "Ephemeral success" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case ephemeral success = flash in the pan.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.