The most common and most likely answer to this crossword clue is the 9 letter word CASSEROLE
I've seen this crossword clue in Financial Times
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More clues leading to the result CASSEROLE
- Part played by civil engineer keeping mug for stew
- Dish inducting fool into Creole cooking
- Hot refreshment in mug during church function
- Stew has turkey in creole cooking
- Bag containing small part for pot
- 1960s’ Mama’s key function? To make stew
- Dish state function involving trace of socialism
- Cook’s part supporting fool in church
- Box holding second part for stewed food
- Dish of cereal cooked with sugar or salt originally
Buddy explains!

The straight part
We know that "Cook" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case cook = casserole.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 CASSEROLE mean?
CASSEROLE noun- A dish of glass or earthenware, with a lid, in which food is baked and sometimes served.
- Food, such as a stew, cooked in such a dish.
- To cook like, or as, a casserole; to stew.