Where poppy seeds might be having a run of success (2,1,4)
I believe the answer is:
on a roll
'having a run of success' is the definition.
(I've seen this before)
I don't understand the remainder of the clue.
Can you help me to learn more?
(Other definitions for on a roll that I've seen before include "Where ham may be" , "Having a run of good luck (colloq.)" , "keeps having repeated wins" , "Where toilet paper may be found" , "Having long spell of good luck" .)