Mushroom Filling 1 tablespoon extra-virgin oil 1/2 onion, finely chopped (use the remaining half for the sauce) 1 garlic clove, finely chopped 250 g saffron milk cap mushrooms (pine) finely chopped - you can substitute with Swiss brown 25 g walnuts, toasted and finely chopped 1 tablespoon white wine 1 tablespoon saffron milk cap (pine