Sift dry ingredients together. Cut in butter until mixture is fine. In a separate, bowl combine eggs,milk,and vanilla. Add half of the liquid to the dry ingredients and beat until smooth. Add remaining liquid and beat until smooth. Pour half the batter into a 9x13 inch pan. In another bowl, combine brown sugar,flour,melted butter,chopped nuts,and cinnamon. Mix into"crumb " mixture. Sprinkle half the crumbs on top of the batter mixture. Pour in the rest of the batter.Sprinkle the rest of the crumb mixture on top. Bake at 350 degrees for 45 to 55 mins.