1
: Combine flour, sugar and cocoa; cut in butter until crumbly. Add egg; mix until well blended. Reserve 1 1/2 cups (375 mL) crumb mixture. Press remainder evenly on bottom of parchment paper-lined 13x9" (3.5 L) baking pan. Bake In preheated 350°F (180°C ) oven 10 minutes.
2
: In heavy saucepan over low heat, combine sweetened condensed milk and 1 cup (250 mL) chocolate chips; stirring until smooth. Spread evenly over prepared crust.
3
: To reserved crumb mixture, add nuts and remaining 1 cup chocolate chips; sprinkle evenly over top. Bake 25 to 30 minutes or until centre is set. Do not overbake. Cool. Cut into bars.