The most common and most likely answer to this crossword clue is the 11 letter word RATATOUILLE
I've seen this crossword clue in The Guardian
R
A
T
A
T
O
U
I
L
L
E
More clues leading to the result RATATOUILLE
- Vegan dish Lauretta mixed with oil
- Artist ate out, possibly consuming bad casserole
- Dish 2 as our little creation
- Dish has Laura and Lottie all of a quiver
- Artist ate out after work, eating bad stew
- Stew a turtle with oil and a caper
- Artist much appreciated struggle by the French to defend refined dish of theirs
Buddy explains!

The straight part
We know that "Dish" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case dish = ratatouille.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 RATATOUILLE mean?
RATATOUILLE noun- A traditional French Provençal stewed vegetable dish consisting primarily of tomatoes, zucchini and eggplant, with other ingredients.