Baker was one producing hit for band (7)
I believe the answer is:
drummer
This clue might be a double definition.
'baker' is the first definition.
The definition and answer can be both people as well as being singular nouns.
Perhaps they are linked in a way I don't understand?
'one producing hit for band' is the second definition.
The answer is a person as well as being a singular noun. This is suggested by the definition.
'was' acts as a link.
Can you help me to learn more?
(Other definitions for drummer that I've seen before include "Band's percussionist" , "Gene Krupa, say" , "eg Ringo" , "salesman to America" , "Group member" .)