Combine Dry Ingredients: In a small mixing bowl, add the flour, pumpkin pie spice, baking soda and salt. Whisk until well combined. Set aside.
Cream Butter and Sugars: In a large mixing bowl, add softened butter and both sugars. Beat on high for 2 minutes until well combined, pale, and fluffy. Scrape down the sides.
Incorporate Egg and Vanilla: Add the egg and vanilla, beating for 15 seconds until well combined.
Mix in Oats: Pour in oats and beat on low speed for 10 seconds until just incorporated into the dough.
Add Flour Mixture: Add the flour mixture, beating for on low speed for 15 seconds until a dough forms without over-mixing.
Raisins: Fold in raisins using a spatula until evenly distributed.
Chill: Cover and chill the dough in the fridge for 30 minutes.
Preheat Oven: While the dough chills, preheat the oven to 156ºF (180ºC) fan-forced. Line a baking sheet with parchment paper and set aside.
Form Cookies: Roll about 1 heaping tablespoon (30g / 1 oz.) of dough into a ball, flatten in your palms and place on the baking sheet. Leave a small gap between each cookie.
Bake: Bake for 10-12 minutes until the edges are golden and the tops are set.
Cool: Allow the cookies to cool on the baking sheet for 5 minutes, then transfer to a wire rack to cool completely before glazing.