Whip up your Christmas veg in no time with Jamie Oliver’s simply but delicious super steamed greens with a clementine and chilli butter. It only takes 10 minutes and can be prepped on Christmas Eve.Whip up your Christmas veg in no time with Jamie Oliver’s simply but delicious super steamed greens with a clementine and chilli butter. It only takes 10 minutes and can be prepped on Christmas Eve.