Base of puddings in the past? (4)
I believe the answer is:
sago
'base of puddings in the past?' is the definition.
The definition and answer can be both substances as well as being singular nouns.
Perhaps you can see an association between them that I don't see?
'base of puddings in the past?' is the wordplay.
'base of' suggests the final letters.
'in the past?' becomes 'ago' ('ago' can be a synonym of 'in the past').
The final letter of 'puddings' is 's'.
's'+'ago'='SAGO'
(Other definitions for sago that I've seen before include "Starchy cereal used in puddings" , "Edible powdery starch" , "Powdery starch from a palm" , "Powdery starch used in cooking" , "Starchy pudding cereal" .)