Finely dice the venison for the farce, chill. Then salt, pepper and finely puree in a blender. Gradually incorporate the cold cream.
Line the terrine mold (about 2 liters capacity) with the bacon slices, leaving about 5 cm overlap, refrigerate. Clean the mushrooms and cut them into coarse pieces (quarter them).
Melt the clarified butter in the pan and fry the mushrooms in it.
Salt, pepper, pour into a sieve and drain well. Salt and pepper the venison fillets. Fry the venison fillets briefly on all sides in the remaining pan fat, remove and allow to cool.
Then brush with the game glace. Blanch the savoy cabbage leaves briefly in boiling salted water and rinse with cold water. Dry well.
Spread the leaves thinly with the farce and roll the fillets in it.
Mix the mushrooms with the farce. Pour some of the farce into the tureen, place the wrapped venison fillet inside and spread the rest of the farce on top. Close with the bacon slices and top with juniper berries, peppercorns, bay leaves and thyme sprigs.
Place the dish in a boiling water bath and cook in a preheated oven at 180°C for about 60 minutes.