In a large bowl, beat butter and sugar until crumbly, about 2 minutes. Add eggs; mix well.
Beat in milk and applesauce (mixture may appear curdled).
Combine the flour, baking powder, salt and baking soda; add to butter mixture just until moistened.
Spread half of the batter into a 13-in. x 9-in. baking pan coated with cooking spray.
Combine filling ingredients; sprinkle half of filling over the batter.
Gently top with remaining batter and filling.
Bake at 350°F for 30-35 minutes or until a toothpick inserted near the center comes out clean. Cool on a wire rack.
Combine icing ingredients until smooth; drizzle over coffee cake and enjoy!