Preheat the oven to 350 degrees.

In a large bowl combine the brown mix, chocolate chips, white chocolate chips, vegetable oil, eggs, and flour. Mix until well combined. Fold in the walnuts.

Line a cookie sheet with parchment paper. Pour the batter onto the parchment and shape it into a 4 x 13 inch log.

Bake for 25-30 minutes or until the cookie log looks cooked. Remove from oven and allow to cool for 5 minutes.

Meanwhile, reduce the oven temperature to 300 degrees.

Remove the brownie biscotti loaf and place on a cutting board. Using a serrated knife, cut into 15 pieces each about 1 inch thick.

Place the pieces cut side up back onto the parchment lined cookie sheet and baked for 12 minutes.

Remove from oven and cool completely.

Place the milk chocolate chips in a microwave safe bowl and microwave in 30 second intervals, stirring in between each heating, until completely melted.

Dip one half of each biscotti into the chocolate and set on a piece of parchment paper. Allow the chocolate to harden for 15 minutes.

Place the white chocolate chips in a microwave safe bowl and microwave in 30 second intervals, stirring in between each heating, until completely melted. Pour into a zip top baggie and snip off the end. Drizzle over the chocolate covered half of the biscotti. Allow the chocolate to harden then store in an air tight container.