The most common and most likely answer to this crossword clue is the 10 letter word FORMIDABLE
I've seen this crossword clue in The Guardian
F
O
R
M
I
D
A
B
L
E
More clues leading to the result FORMIDABLE
- Awesome story about soldiers mentioned in dispatches at the front
- Model bra, if bust awesome
- Dreadful story about gold, stupid when written up
- A bid failing, last of coal seen in mine? That’s daunting
- Awe-inspiring tale about soldiers and shadowy uprising
- Record I had accomplished hard to beat
- . Sit back to gain muscle after body becomes strong
Buddy explains!

The straight part
We know that "daunting" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case daunting = formidable.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 FORMIDABLE mean?
FORMIDABLE adjective- Causing fear, dread, awe, or discouragement as a result of size, strength, or some other impressive feature; commanding respect; causing wonder or astonishment.
- Difficult to defeat or overcome.