Embarrassed as stooge goes outside before sunrise (7)
I believe the answer is:
predawn
'before sunrise' is the definition.
'embarrassed as stooge goes outside' is the wordplay.
'embarrassed as' becomes 'red' (someone may blush or go red when embarrassed. I am not sure about the 'as' bit.).
'stooge' becomes 'pawn' (I've seen this in another clue).
'goes outside' indicates putting letters inside.
'red' put within 'pawn' is 'PREDAWN'.
Can you help me to learn more?
(Other definitions for predawn that I've seen before include "Before first light" , "when the night is very far spent" , "Before the sun begins to rise" .)