Preheat the oven to 180°C (fan oven 160°C), gas mark 4.
Soak the dried mushrooms in 300ml (1/2 pint) warm water for 20 mins. Drain, reserving the liquid, and finely chop.
In a large casserole, melt the butter and brown the pheasant pieces well on all sides. Remove with a slotted spoon and set aside.
Add the juniper berries to the pan with the onions and bacon and fry gently for 10 mins until golden.
Stir in the soaked mushrooms and flour, followed by the wine and stock. Bring to the boil, return all the pheasant pieces, cover and cook in the preheated oven for 25 mins.
Uncover the casserole, stir in the button mushrooms, cover again and return to the oven for a further 20-25 mins until very tender.
Using a slotted spoon, transfer the contents of the casserole to a warm platter leaving the cooking juices behind. Cover and keep warm.
Bring the cooking juices to the boil and stir in the conserve. Add a little of the mushroom soaking liquid if needed. Bubble for 1-2 mins, then spoon over the pheasant and serve.
To make this casserole ahead, cook the pheasant up to the end of the recipe the day before. Cool, cover and keep chilled. To use, return the casserole to the boil, cover and simmer very gently on the hob for 10-15 mins or until piping hot.
When pheasant is out of season, use small guinea fowl.