Step 2. Place chocolate chips in a microwave-safe bowl. Heat in 30-second increments in the microwave. Repeat this process until chocolate is almost completely melted. When it's at this stage, continue to stir until all of the chocolate is completely melted.
Step 3. Repeat the same process with the white chocolate, placing white chocolate in a bowl and heating it in the microwave, stirring frequently. When white chocolate is completely melted and smooth, set it aside.
Step 4. Pour dark chocolate onto baking sheet and spread evenly with an offset spatula or back of a large spoon. Drizzle white chocolate all over dark chocolate. Working quickly, use a knife to make pretty swirls throughout chocolate.