Paint it out, that's all! (3)
I believe the answer is:
pan
'that's all' is the definition.
I can't judge whether this defines the answer.
'paint it out' is the wordplay.
'out' indicates named letters should be taken away.
'paint' with 'it' removed is 'PAN'.
Can you help me to learn more?
(Other definitions for pan that I've seen before include "Toilet bowl" , "Sweep" , "search for gold and > god" , "Wash gravel" , "Arcadian god" .)