Dice all the game except the mallard leg meat into 1-inch cubes. Coat the meat in seasoned flour and fry off until crisp and fully cooked. Place the meat in a pie dish.
Slice the onions and fry them in a little oil until softened. Add the mushrooms and, when golden brown, tip the mushrooms and onions over the top of the meat.
Heat up the game stock and add a little redcurrant jelly to sweeten before pouring over the pie mix. Leave the pie mix to cool and add the mallard leg meat.
Cover the whole pie dish with the pre-rolled pastry and brush the top with egg yolk. Bake for 40 minutes in an oven pre-heated to 180°C/Fan 160°C/Gas 4.
While the pie’s in the oven, peel the red skin potatoes and boil until soft, then mash with the butter and milk. Add 1 tbsp of mustard, or more to taste. Season with salt and white pepper.
To make the gravy, pour the ale into a saucepan on a high heat and reduce it by half. Add the 200ml of game stock and thicken with the gravy granules.
Finally, prepare the broccoli. Rub oil into the broccoli then drop into a very hot pan. Sear until it begins to wilt and slightly blister.
Serve the pie as a centre piece alongside serving dishes of the mustard mash and broccoli. Finish with a big jug of your ale gravy.