Preheat the oven to 350 degrees. Line a large baking sheet with parchment paper.

Whisk together the flour and baking powder in a medium bowl.

Add sugar, butter, lemon zest, and salt to a stand mixer. Mix on medium speed until light and fluffy.

Add the eggs one at a time, scraping down the sides between additions. Next, add the flour mixture and mix on low speed just until incorporated.

Use a wooden spoon to stir in the pistachios and cranberries. Empty the dough onto the parchment paper lined baking sheet.

Form the dough into a 15-inch long, 3-inch wide log.

Bake for 40 minutes, or until golden. Cool on the pan for 30 minutes.

Carefully place the biscotti log onto a cutting board. Using a serrated bread knife, cut into ? to ?-inch slices.

Place the slices back on the baking sheet and return to the oven for 15 minutes.

Carefully transfer the biscotti to a wire rack and cool completely before dipping in chocolate.

Melt chocolate chips per the package directions, stirring until smooth.

Dip one half of each cookie into the melted chocolate and gently shake off the excess. Place the biscotti on wax paper and sprinkle with jimmies, if desired. Refrigerate the cookies until the chocolate is firm before storing.