Rather too much from a flat out confection (2,1,5)
I believe the answer is:
to a fault
'rather too much from' is the definition.
I can't judge whether this definition defines the answer.
'a flat out confection' is the wordplay.
'confection' is an anagram indicator (I've seen this in other clues).
'a'+'flat'+'out'='aflatout'
'aflatout' is an anagram of 'TO A FAULT'.
Can you help me to learn more?
(Other definitions for to a fault that I've seen before include "Where bad service leads" , "unduly" , "bad driver finally disqualified, taking blame" , "Excessively, like being too generous" , "Excessively, like over-generosity" .)