Begin by preheating your oven to 350 degrees.

In a large mixing bowl, use a hand held mixer to beat together the egg, sugar, and baking powder.

Next, add in the pumpkin puree, pumpkin spice, salt, and vanilla extract. Beat to incorporate.

Use a spatula to carefully fold in the flour until just incorporated.

Line a baking sheet with parchment paper and shape the dough into a flat log; the log should measure roughly 3x8 inches.

Bake for 40 minutes and remove from the oven. Lower the temperature of your oven to 300 degrees.

Allow the log to cool down for at least 20 minutes. Then, carefully slice across the log using a serrated knife; cut into half inch slices.

Lay the slices flat on the baking sheet and return them to the oven for 15 minutes; turn the slices over and bake for an additional 15 minutes.

Once completely cooled, melt the dark chocolate chips and drizzle over the biscotti.

Place in the refrigerator to firm up. Store in an air-tight container.