Melt half the butter in a pan. Add the onion and fry
over a low heat until soft, but not browned.
Stir in
the
breadcrumbs, lemon rind and herbs and season to
taste with salt and pepper. Bind with a little
beaten egg.
Remove from the heat and leave to cool. Slit the pork fillets lengthways without cutting right
through them and flatten the meat until the fillets
lie flat.
Arrange the stuffing on top of one of the
fillets turning in the ends. Lay the second fillet
on top also tucking in the ends and wrapping the
long sides around to enclose the stuffing. Tie at
intervals with string.
Melt the remaining butter in
an ovenproof dish. Add the fillets and brown them
allover. Pour in the water, cover tightly and cook
in a preheated oven, 180°C (350°F), Gas Mark 4, for
1-1 1/4hours.
Remove the string and transfer
to a warmed serving dish.
Blend the arrowroot with the stock and stir into the
cooking juices, then taste and adjust the seasoning
if necessary.
Serve the fillet carved in slices and
accompanied by apple sauce.