Chocolate Raspberry Layer Bars

1-2/3 cups (400 ml) graham cracker crumbs
1/2 cup (120 ml) butter or margarine, melted
12 oz (336 g) semi-sweet chocolate chips, divided (2 cups / 480 ml)
2-2/3 cups (640 ml) flaked coconut (7 oz / 196 g)
14 oz (392 g) can sweetened condensed milk (1-1/4 cups / 300 ml)
1 cup (240 ml) seedless red raspberry jam
1/3 cup (80 ml) finely chopped walnuts (optional)
1/3 cup (80 ml) white baking chips

Combine graham cracker crumbs and butter in medium bowl.
Press firmly onto bottom of ungreased 13x9-inch (32.5x23-cm) baking pan.
Sprinkle with 1-1/2 cups (360 ml) semi-sweet chocolate chips, then coconut;
 pour sweetened condensed milk evenly over top.

Bake in preheated 350 F (180 C) oven for 20 to 25 minutes or until
lightly browned; cool completely in pan on wire rack.

Spread jam over cooled top; sprinkle with walnuts. 
 Place remaining semi-sweet chocolate chips 
and white baking chips in separate heavy-duty plastic bags. 
 Microwave together on medium-high (70%) power for 45 seconds; knead bags to mix.
Microwave at additional 10-second intervals, kneading until smooth. 
 Cut a small hole in corner of each bag; squeeze to pipe over bars.

  Refrigerate for 5 minutes to set chocolate.  Cut into bars.

Makes 2 dozen bars.