Preheat oven to 375ºF (190°C). Prepare a baking sheet with parchment paper.

Using an electric mixer, cream together softened butter and brown sugar for 3 minutes until light and fluffy. Add vanilla and egg and mix again until combined. Then add in pumpkin and beat on low until combined. (You might have streaks of butter throughout instead of it being fully combined - this is okay and will correct itself once you add flour.)

In another bowl, whisk together the flour, spices, baking soda, salt and oats.

Add about ½ cup of dry ingredients to your wet ingredients at a time, mixing on low until well mixed.

Use a cookie scoop or two spoons to scoop dough onto baking sheet. The dough will be quite wet. If you prefer flattened cookies versus more rounded ones, you can flatten the dough slightly with a spatula or your hand.

Bake in preheated oven for 10-12 minutes until the cookies spring back when touched. Cool fully on a wire rack before drizzling icing on top.