Prepare 9 x 11 baking dish  by covering in foil and spraying with non stick spray.

Melt milk chocolate chips, reserving 1/2 cup, in microwave. Cook on high for 90 seconds, stir, and continue for another 60 seconds. Remove from microwave and stir continuously until melted. Don't try to completely melt the chocolate in the microwave.  If it gets too hot, it will seize up and become fudge-like never to go back to a melted state again.   Microwave cook times do vary so keep an eye on your chocolate.

When melted, pour into pan and smooth.

Melt white chocolate and peanut butter in microwave for 90 seconds. Remove and stir. Melt 60 seconds more, remove and stir continuously until completely melted. Pour over milk chocolate and carefully smooth trying not to combine the layers. If they get mixed, it's no crime.

Melt reserved milk chocolate chips in microwave for 60 seconds. Remove and stir continuously until completely melted. Drizzle over peanut butter mixture.

Sprinkle peanuts on top of chocolate and gently press into soft chocolate. Place into freezer until hard.

Cut into pieces.  Store in refrigerator unless you eat the whole batch at once.