Very easy, apologies for vague quantities - its been rather drastically adapted from my original recipe (which was for a Christmas suet pudding . . .)
Put a good handful of dried mushrooms on to soak in hot water
Fry a couple of leeks (or onions if you prefer) and quite a lot of normal mushrooms in olive oil until soft but not too cooked, add some crushed garlic if you like
Spread the mushrooms/leeks out in a pie dish, drain a tin of artichoke hearts, halve and dot around all over the mushroom/leek mixture.
Strain the dried mushrooms keeping the liquid, and scatter those over too.
Then make a gravy - fry a tablespoon of cornflour in a couple of tablespoons of olive oil, add the mushroom soaking liquid and a big glass of red wine, and then a little more water if needed to make up a reasonable amount of 'gravy'. Add a good splash of soy sauce to taste. Cook til thickened
Pour around half the thickened gravy over the contents of the pie dish, top with puff pastry. At this point it can go in the fridge til ready to cook. Cook for about 20 mins on a high-ish heat. (I've got a rayburn, so don't do exact temps, but whatever you'd cook pastry on normally.) Heat the rest of the 'gravy' and serve with the pie.