Prepare the stuffing mix as per the instruction on the pack and allow to cool.
Place the fillets on a chopping board; place them "top to tail" so that there is a thick end and tail end together.
Lay the stuffing mix on top of one of the fillets, cover the stuffing with the other fillet. Tie with string loosely so as not to squeeze out any of the stuffing.
Place on an oiled baking tray. Insert the rosemary sprigs under the string ties and season with salt and pepper.
Roast in a hot oven 180C for 10 to 15 minutes; remove when cooked.
Place the monkfish portions on a warm tray. De-glaze the cooking tray with a little white wine and reduce right down.
Add the chopped rosemary and fresh cream; blend into a sauce. Remove any string from the fish, cut into slices and serve with a drizzle of sauce.