Preheat the oven to 400 degrees.
Cut six pieces of parchment or aluminum foil into ovals about thirteen inches at the widest point.
Cut the sole fillets in half.
Place a slice of ham on half of each piece of parchment or foil.
Top the ham with a slice of sole.
Dot the fish liberally with one quarter cup of the butter.
Sprinkle with salt, pepper, thyme and parsley.
Fold the other half of the parchment over and twist the edges to seal the ends envelope-fashion.
The edges must be thoroughly sealed to enclose the juices as the food cooks.
Place the packets in a shallow pan and bake fifteen minutes.
Meanwhile, melt the remaining one quarter cup of butter and season to taste with lemon juice.