A little of this, a little of that (5)
'a little of this a little of that' is the definition.
(I've seen this in another clue)
This is all the clue.
(Other definitions for olio that I've seen before include "Mixture" , "Collection of miscellany" , "Variety" , "Savoury dish of different types of meat and vegetable" .)
(Other definitions for blend that I've seen before include "union" , "Mix together" , "Combine together" , "Mingle" , "Coalesce" .)