I always keep a tin of this pesto in a plastic container. So long as covered in the oil it keeps and is extremely useful when nothing left in the fridge!
Pour some extra virgin olive oil into a sautéing pan. Add some diced onion and garlic. Allow to sweat and add some button mushrooms stirring occasionally. Pour in a good glass of wine and gently simmer. Add some walnuts and pesto.Stir and serve with wholemeal bread and the rest of the bottle!