Split peas cooked with speed (8)
I believe the answer is:
separate
'split' is the definition.
(I know that split can be written as separate)
'peas cooked with speed' is the wordplay.
'cooked' indicates an anagram (letters cooked into a new form).
'with' is a charade indicator (letters next to each other).
'speed' becomes 'rate' (both can mean pace).
'peas' anagrammed gives 'sepa'.
'sepa'+'rate'='SEPARATE'
(Other definitions for separate that I've seen before include "Different, distinct" , "Standing apart" , "Not joined or touching" , "divorce" , "Divided -- distinct" .)