Line a rimmed baking sheet with parchment or waxed paper. Set aside
In a large mixing bowl, place white chocolate chips or almond bark. Place the bowl in the microwave for about one minute. Stir well. Microwave at 30 to 45-second intervals, stirring after each, until it's melted and smooth.
3 cups white chocolate chips
Stir in peanut butter until melted and well blended.
1/2 cup creamy peanut butter
Spread out onto the waxed paper-lined baking pan.
Place chocolate chips in a small bowl and microwave at 30 to 45-second intervals, stirring after each, until smooth and melted.
1 cup semi-sweet chocolate chips
Drop dollops of chocolate onto the white chocolate mixture in the pan. Swirl with a butter knife to create a marbled look.
Place the baking sheet in the refrigerator until hardened or allow it to harden completely at room temperature.
Break into pieces and store in an airtight container.