Pulse biscoff cookies in the food processor until they form a fine crumb. Set aside 1 tbsp of crumbs for later.
Add the rest of the crumbs to a large mixing bowl along with the pumpkin puree, maple syrup, cinnamon, nutmeg and ground ginger. Mix until everything is combined - it will be crumbly at first but soften up and combine well as you mix.
Scoop a heaping 1 tbsp per truffle onto a parchment lined baking sheet and set in the freezer for 45 minutes.
After 45 minutes, Melt the chocolate chips in the microwave in 20-30 second increments, stirring after each 20-30 seconds, Let the melted chocolate sit for a few minutes before dipping the truffles in.
Dip each truffle into the melted chocolate, letting the excess chocolate drip off add back to the parchment lined baking sheet. You can also drizzle the chocolate over some of the fully dipped truffles and just drizzle over some of the truffles instead of fully dipping. Either way, as you decorate the truffles, make sure to sprinkle over a bit of the leftover cookie crumbs to finish. Put back in the fridge for 30 minutes to finish setting.
Store in a parchment paper lined airtight container in the fridge for up to 7 days. They can sit out for a few hours at a time if you're serving for dessert or at a party.
Notes
Decorate the tops of the pumpkin truffles with gold sprinkles before the white chocolate sets for an extra fancy topping.
You can substitute the spices in this recipe with 1 1/4 tsp pumpkin pie spice if desired.
If you don't have a food processor to crush the biscoff cookies, add them to a large ziplock bag and use a rolling pin to crush the cookies into very fine crumbs.