The most common and most likely answer to this crossword clue is the 9 letter word LEAVENING
I've seen this crossword clue in The Guardian
L
E
A
V
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Buddy explains!

The straight part
We know that "Raising dough" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case raising dough = leavening.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 LEAVENING mean?
LEAVENING verb- To add a leavening agent.
- To cause to rise by fermentation.
- To temper an action or decision.
- To imbue; to infect; to vitiate.
- To rise or become larger.
- The process by which something is leavened.
- Making light by aeration.
- Any organism or substance added to a food product (such as dough or batter) that makes it rise when cooked.