Bank on the Spanish producing comic verse (8)
I believe the answer is:
doggerel
'comic verse' is the definition.
(I've seen this before)
'bank on the spanish' is the wordplay.
'bank' becomes 'dogger' (I have seen 'A bank' mean 'dogger' so perhaps 'bank' could also mean 'dogger').
'on' is a charade indicator (letters next to each other).
'the spanish' becomes 'el' ('the' in Spanish).
'dogger'+'el'='DOGGEREL'
'producing' acts as a link.
(Other definitions for doggerel that I've seen before include "Nonsense verse" , "Unpretentious verses" , "Bad verse - of canine beginnings?" , "Unpretentious verse" , "trivial lines" .)