Sweet Potato Casserole

This is one of my Mom's favorite Thanksgiving/Christmas casseroles. You have GOT to try it!

Ingredients:
3 c. mashed sweet potatoes
1/2 stick melted butter
1 c. sugar
1 Tb. vanilla
1/2 c. milk
2 eggs
1/2 tsp. salt

Topping:
2 1/2 Tb. butter
1 c. chopped nuts (walnuts)
1/2 c. brown sugar
1/2 c. flour

Directions:
Mix all ingredients together, pour into a casserole dish. Put on topping. Bake at 350 degrees F for 25 minutes.