In a large bowl mix the pumpkin and brown sugar. Add the flours, baking soda, baking powder, salt and oil and mix with a spoon until you get a smooth dough.
Add chopped walnuts and chocolate and stir to distribute them evenly.
Wet your hands and form the cookies, lay them on a baking tray lined with parchment paper.
Put the cookies in the fridge for one hour to rest then bake at 360°F for 15 minutes.
Note
These pumpkin chocolate cookies keep well in a tin or glass container for two weeks.