The most common and most likely answer to this crossword clue is the 10 letter word FLORENTINE
I've seen this crossword clue in The Guardian
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More clues leading to the result FLORENTINE
- Italian let in to break the ice
- Italian learning coming with set of books with beautiful binding
- Eg Dante let Inferno become convoluted
- Wonderful outstanding actor beginning in theatre, Italian
- Cook it with fennel or with spinach
- Iron shackling Italian actress, metal is Italian
- See payment for accommodation accepted by upstanding Italian city-dweller
- Italian‘s decent housing cheap to lease, not wide
Buddy explains!

The straight part
We know that "with spinach" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case with spinach = florentine.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 FLORENTINE mean?
FLORENTINE noun- A biscuit consisting mostly of nuts and preserved fruit, usually coated with chocolate on one side.
- A kind of durable silk.
- A kind of pudding or tart or meat pie.
- Cooked or served with spinach.