My sister-in-law gave me this recipe, I think she got it from the Food Network. I have changed it just a bit. This is my favorite way to make Halibut, but any firm whitefish will do. I serve this to guests all the time.
Place the flour in a shallow bowl and season with salt and pepper. In another shallow bowl, beat the eggs with the mustard. In a third shallow bowl, place the dried mashed potato flakes.
In a large sauce pan, heat oil over high heat.
Dip the steaks in the the flour, then the egg mixture, then the potato. Place the fish in the sauce pan and sear for 2 minutes per side. Place the saucepan with fish in the oven for 4 minutes or until cooked throughly.
While fish is baking. Place anouther saucepan over high heat. Add the wine, lemon juice, garlic and green onions. Cook for 5-6 minutes until the liquid is reduced by 2/3.
Over low heat whisk in butter, a small amount at a time.