The most common and most likely answer to this crossword clue is the 7 letter word OROGENY
I've seen this crossword clue in Financial Times
O
R
O
G
E
N
Y
Buddy explains!

The straight part
We know that "Outcome of smashing plates" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case outcome of smashing plates = orogeny.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.
What does OROGENY mean?
OROGENY noun- The process of mountain building by the upward folding of the Earth's crust.