Omelet: Heat oven to 325 degrees F. Butter a 12 x 7-inch baking dish.
Melt 3 tablespoons butter in a saucepan. Blend in flour, mustard and pepper.
Add milk gradually, stirring constantly until sauce is thickened. Cool slightly.
Beat egg yolks until thick. Add sauce to egg yolks. Beat egg whites and
1/2 teaspoon salt until stiff peaks form. Gently fold into sauce.
Pour mixture into the prepared baking dish and bake for 20 minutes, or until
knife inserted in center comes out clean.
Serve in baking dish immediately with Crab Newburg Sauce.
Crab Newburg Sauce: Melt butter in a skillet and gently cook onions and
mushrooms until soft. Add flour, salt, paprika and pepper. Gradually add milk
and Worcestershire sauce and cook, stirring constantly, over medium heat until
thick and bubbly. Remove from heat and cool slightly. Stir in beaten egg yolks.
Add white wine and crab meat.
Keep warm in the top of a double boiler until serving time.