Green trattoria topping (5)
(Other definitions for pesto that I've seen before include "Basil-based sauce" , "Italian sauce containing basil" , "Basil and pine nut sauce" , "Sauce of basil, pine nuts and garlic" , "Pasta sauce variety" .)
(Other definitions for oregano that I've seen before include "Aromatic culinary herb" , "Herb - a no-goer (anag)" , "Gear Ono up for the herb" , "Marjoram-like herb" , "Mediterranean herb" .)