Preheat your oven to 350°F (175°C).
In a mixing bowl, combine pumpkin puree, brown sugar, and sugar, and mix well.
Add the oats, flour, baking soda, cinnamon, nutmeg, and salt to the mixture.
Stir until all ingredients are thoroughly combined.
If using, fold in raisins or chocolate chips.
Drop spoonfuls of dough onto a baking sheet lined with parchment paper.
Bake for 12-15 minutes until edges are golden.
Remove from the oven and let cool on a wire rack.
Enjoy your pumpkin oatmeal cookies warm or at room temperature!