Preheat oven to 350°. Place a greased 9-in. springform pan on a double thickness of heavy-duty foil (about 18 in. square). Securely wrap foil around pan. In a large bowl, combine cookie crumbs, walnuts, sugar, cinnamon and butter. Press onto bottom and 2 in. up sides of prepared pan., In a large bowl, beat cream cheese and sugar until smooth. Beat in milk, flour and vanilla. Add eggs; beat on low speed just until combined. Pour into crust. , Pour dulce de leche into a microwave-safe bowl; microwave at 50% power until softened. Drop dulce de leche by tablespoonfuls over batter; cut through batter with a knife to swirl. , Place springform pan in a large baking pan; add 1 in. of hot water to larger pan. Bake 60-70 minutes or until center is just set and top appears dull. , Remove springform pan from water bath. Cool on a wire rack 10 minutes. Carefully run a knife around edge of pan to loosen; cool 1 hour., In a microwave-safe bowl, melt chips; stir until smooth. Stir in chili powder. Spread over cheesecake. Refrigerate overnight. Remove sides of pan. , In a small bowl, whisk dulce de leche and hot water until smooth; drizzle over cheesecake.