Heat oven to 350 degrees and grease a 9 inch springform pan. Lightly flour.
Microwave milk and chocolate chips in small bowl uncovered on med about 1 minute or until chocolate is melted.
Beat dry cake mix and oil in large bowl on low speed 30 seconds. mix will be crumbly, reserve 1 cup. Beat applesauce and eggs into remaining cake mixture on low speed 30 seconds, then beat on medium speed 2 more minutes. Spread in pan.
Drop chocolate and milk mixture by teaspoonfuls over batter, dropping more around the edge than in the center. Stir nuts into reserved 1 cup of cake mixture and sprinkle over batter.
Bake 45-50 minutes or until center is set. Cool 10 minutes. Remove sides of pan and cool completely. About 2 hours. Drizzle with frosting if desired. Store covered.