Red Lobster's Crab Au Gratin

I received an email today from Recipe Robot and this is one of the featured recipes.

• Ready In: 35 mins
• Serves: 6-8
• Yields: 1 9 x 13 inch pan

Ingredients

• 8  tablespoons butter, 1 stick
• 1⁄2 cup onion, minced
• 2  tablespoons all-purpose flour
• 1  cup milk, scalded
• 1⁄2 teaspoon salt
• 1  dash white pepper
• 1⁄4 cup sherry wine
• 12  ounces  crabmeat
• 1  cup  cracker, finely crumbled
• 1⁄2 cup cheddar cheese, finely grated

Directions

1. Preheat oven to 350 degrees.
2. Crumble crackers between waxed paper with a rolling pin. Reserve just enough crumbs and cheese to top the casserole.
3. Melt 4 tablespoons of the butter in a large heavy skillet. Add onion and saute for about 5 minutes or until golden. Slowly add flour, stirring constantly over low heat. When flour is blended, gradually add hot milk (scalded) and blend with a whip. Continue stirring over low heat until the sauce begins to thicken.
4. Add salt, pepper, and sherry and continue stirring in a bowl.
5. Mix crab meat, sauce and the extra cracker crumbs and cheese. Place in a lightly greased baking dish. Sprinkle reserved cracker crumbs and cheese on the top of the casserole. Dot the top with the remaining 4 tablespoons butter.
6. Bake uncovered for about 15 minutes or until the top is golden brown.