Mushroom Stroganoff Pie

I was driving home yesterday, trying to think of a recipe idea that would use up the mushrooms and onions sitting around in the fridge. The obvious idea was a mushroom stroganoff, but seeing as my wife has just come back from India, rice was off the menu for a bit. As an alternative I thought about serving it up with mash and then realised that I could combine the two to make a rather delicious mash topped pie. Here's the result:

Mushroom Stroganoff Pie
Serves 5-6
Preparation time: 20mins
Cooking time: 15mins

Ingredients:
For the filling:
14oz (400g) Button Mushrooms
14oz (400g) Chestnut Mushrooms
16fl oz (500ml) Double Cream
4 Medium White Onions
Worcestershire Sauce
Small knob of butter
Optional: A small packet of mixed dried wild mushrooms

For the topping:
4 large baking potatoes
4oz (110g) Salted Butter
Splash of Milk
A pinch of salt

Method:

1. Fill the kettle and set it boiling.
2. Chop the potatoes into chunks (peel if you're not a fan of the skins).
3. Optional- Soak the dried mushrooms for ten minutes in boiling water.
4. Put the potatoes in a pan of boiling water and simmer for 15 minutes.
5. Very finely dice the onions and mushrooms.
6. Melt a knob of butter in a large pan and add the onions. Fry until transparent then add the mushrooms. Stir until softened.
7. Preheat oven to 180 degrees C.
8. Add the cream and worcestershire sauce to taste (I like it so that you can just get the tanginess of the sauce as an after taste. Simmer for 5 minutes to reduce the cream to a thicker consistency.
9. Drain the potatoes, add the butter, salt and milk and mash until creamy.
10. Pour the sauce into a deep lasagne dish and top with the mash. Use a fork to score lines in the mash.
11. Place the pie on a middle shelf in the oven and cook for 10 minutes.
12. Switch the oven's grill on and continue to cook for another 5 minutes.

Variations:

My wife suggested that some brocolli that had been sitting in the fridge would have worked too (I had my stroganoff blinkers on it would appear) and I might consider peas or sweetcorn in the mix next time. For a "chicken and leek" pie, add in some sliced Quorn chicken fillets and coarsely sliced leeks in place of the onions and half of the mushrooms.