Seafood En Papillote

• 4 flounder fillets
• 2 egg yolks
• 2 green onions
• 475 ml fish stock
• 130 gr sea scallops
• 120 gr shrimp
• 40 gr mushrooms
• 60 ml dry wine salt pepper (white freshly ground)
• 32 gr flour
• 28 gr butter