1/2 c Butter, softened 1/2 c Packed brown sugar 1 c Mashed,cooked sweet potatoes 3 Eggs,lightly beaten 1/3 c Corn syrup 1/3 c Milk 1/2 t Salt 1 t Vanilla extract 1 Unbaked pie shell Cream butter and brown sugar in bowl until light and fluffy.Blend in sweet potato and eggs.Add next 4 ingredients;mix well.Pour into pie shell.Bake in a 425 degree oven for 10 minutes.Reduce heat to 325 degrees and bake 35 to 45 minutes longer or until well set.