1
: Preheat oven to 350°F. Place toffee and 1?3 cup evaporated milk in the top of a double boiler or heat-proof medium bowl set over boiling water. Cook, stirring occasionally, for about 30 minutes or until completely melted and smooth.
2
: Meanwhile, in a large bowl, stir cake mix, butter and remaining evaporated milk until smooth. Stir in pecans. Press 2 cups of cake mixture into the bottom of a parchment paper-lined 13 x 9 inch pan. Bake 10 minutes. Sprinkle chocolate chips evenly over cake base. Spread toffee mixture over top. Crumble remaining cake mixture evenly over toffee. Bake in centre of oven for about 15 minutes, or until lightly browned around the edges. Cool in pan on rack. Refrigerate for about 2 hours, or until firm. Lift out of pan onto cutting board. Cut into bars.