1. Preheat the oven to 170C fan-forced (190C conventional).

2. Add the olive oil and butter to a large frypan over medium heat. Once foaming, add the onion and leek. Cook for 2 minutes then add the garlic and cook until the leeks are soft, and the onions are completely cooked through and translucent (about 2 minutes). Add the paprika and briefly stir to coat.

3. Add the mushrooms and cook until soft, about 3-5 minutes.

4. Add the stock and cook until the stock has mostly been absorbed and evaporated (about 10 minutes).

5. Add the tomato paste and then the cream and turn down to a simmer. Cook until the mixture has reduced again and the cream sauce is a lovely thick consistency (about 8 minutes but keep an eye on it). Season generously.

6. Scoop your mushroom mixture into your pie dish of choice. Cut a piece of puff pastry to fit your cooking mould (I cut discs to the size of my individual little tins). Place on top of the mushroom mixture and press down gently. 

7. Brush the pastry tops with the eggwash and place in the oven for 20-30 minutes or until the pastry has puffed and taken on a beautiful golden hue. Best eaten piping hot.

Note: Given the pastry essentially just sits on top of the mixture and puffs, you aren't limited to the cooking vessel by any means. I made these pies in individual roasting dishes, but you really could use anything, such as a Pyrex baking dish or individual pie moulds.