Butter a baking dish about 12 X 7 X 2 inches.
Sprinkle green onions into dish.
Split sole fillets in half lengthwise and trim so pieces are all about the same size.
You should have about 16 narrow strips.
Save the trimmings to make the stock as directed later.
Sprinkle trimmed pieces of fish with salt and pepper and roll up so they are the shape of cinnamon rolls.
Fasten each roll with a toothpick.
Set them in baking dish on top of green onions.
Refrigerate while preparing stock.
Combine fish trimmings, onion slice, parsley, lemon juice, water and wine in small saucepan.
Bring to a boil, turn down heat, cover and simmer 30 minutes.
Strain.
Pour over fish rolls.
Heat oven to 350 degrees.
Cut a piece of heavy brown paper just the right size to fit inside the baking dish.
Butter it well and lay it over the fish (don't use foil, it may discolor the fish).
Bake 15 to 20 minutes or until fish flakes easily with a fork.
Lift fish rolls out of pan with a slotted spoon.
Drain liquid from pan.
Remove toothpicks from fish, return to pan and keep warm.
Strain liquid.
Melt butter in small saucepan.
Sprinkle in flour and let bubble up.
Remove from heat and add fish cooking liquid all at once.
Stir to blend.
Return to moderate heat and cook, stirring constantly, until thickened.
Beat cream and egg yolk together and stir into sauce.
Simmer fresh green grapes in 1/4 cup boiling water 2 minutes and drain.
Or drain canned grapes.
Put grapes around fish.
Pour sauce over all.
Slip under broiler.
Brown lightly.
Serve immediately.