I've made this a few times and it a great dessert. Change the flavors of ice cream if you wish-I do. It is a bit of work, and I've included the chilling time with prep time. The original post came from Cookin'Mom.
Line 2 rectangular pans, 13x9x2 inches, with aluminum foil, leaving 1 inch of foil overhanging at 2 opposite sides of pan.
Melt chocolate chips and the 2 T. shortening in a 1 quart saucepan over low heat, stirring frequently, until melted.
Divide the melted chocolate evenly between the 2 pans and spread into thin, even layers.
Freeze for 10 to 15 minutes.
Remove the foil sheets of chocolate from the pan and return to the freezer.
Prepare pans with foil again.
Melt the white baking chips with the 2 T. shortening over low heat, stirring frequently, until melted.
Divide melted mixture evenly between the 2 pans and freeze for 10 to 15 minutes.
Remove the foil sheets from pan and return to freezer.
Line 1 rectangular pan, 13x9x2 inches, with plastic wrap and set aside.
Beat half of the ice cream with half of the peanut butter in a large bowl on medium speed until just mixed.
Repeat with remaining ice cream and peanut butter in second bowl.
Remove all chocolate layers from freezer and carefully peel foil from layers as it is used.
Place 1 white chocolate layer in bottom of plastic wrap lined pan.
Carefully spread on 1/3 of the ice cream mixture.
Add 1 semisweet layer, spread with 1/3 of the ice cream mixture.
Repeat, ending up with the last layer being the semisweet chocolate layer.
Cover and freeze for at least 12 hours.
Place pan upside down on a cookie sheet.
Place hot towels on bottom of pan.
When just warm you should be able to remove pan and plastic wrap.
At this point you can top with whipping cream, mint leaves and cocoa powder to dust, or cut into 5 rows by 3 rows, and garnish with a dolop of whipped cream, mint leaves or chocolate leaves and a dusting of cocoa powder.