The most common and most likely answer to this crossword clue is the 9 letter word CORNFIELD
I've seen this crossword clue in The Times
C
O
R
N
F
I
E
L
D
Buddy explains!
The straight part
We know that "I’m all ears!" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case i’m all ears! = cornfield.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 CORNFIELD mean?
CORNFIELD noun- A field of corn, wheat or other cereal crop