Combine the sugar and coconut oil in a large bowl and mix well.
Add the pumpkin and mix it well again.
Add the flour, egg, and salt and mix it once more.
Add the baking powder and fold it well.
Make a ball of dough and let it refrigerate for 30 minutes.
Roll out the dough on a flat surface with the help of a rolling pin.
Use a cookie cutter to cut the cookies and bake them in a preheated oven at 170º for 7 minutes. If you don't have a cookie cutter, use the top part of a glass.
Take them out of the oven and let them cool completely.
Fill with the peanut butter and serve.
For an even better (and tastier) result, refrigerate them for 1 hour before serving.