The most common and most likely answer to this crossword clue is the 5 letter word MUNCH
I've seen this crossword clue in The Times
M
U
N
C
H
More clues leading to the result MUNCH
- Champ, from German city one knocked out
- Artist's champ
- To chew noisily gets one thrown out of German city
- Get one's teeth into eminent expressionist
- Bavarian capital not allowing one to eat noisily
- Scream he produced, almost stabbed by knight
- Noisily eat lunch, enjoying different starter
- Chew lots, swallowing some number
- Chew a lot, swallowing quarter of the nuts
- Chew meal, having changed starter
Buddy explains!

The straight part
We know that "Get one's teeth into/eminent expressionist" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case get one's teeth into/eminent expressionist = munch.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 MUNCH mean?
MUNCH noun- A location or restaurant where good eating can be expected.
- An act of eating.
- Food.
- (BDSM) A casual meeting for those interested in BDSM, usually at a restaurant. See Munch (BDSM).
- To chew with a grinding, crunching sound, and with the mouth closed — often used with on.
- To eat vigorously or with excitement.