Catfish In Oyster Andouille Butter

• 24 shucked oysters (fresh)
• 1 egg
• 240 gr eggwash
• 180 ml vegetable oil
• 120 ml milk
• 120 ml dry wine (white)
• 100 gr catfish fillets
• 65 gr unseasoned flour
• 60 gr green onions (chopped)
• 45 gr mushrooms (sliced)