Preheat oven to 350 degrees.
In the bowl of your stand mixer with the paddle attachment, beat butter and sugars over medium speed until smooth. Add egg and vanilla extract and beat until combined.
In a separate bowl, combine flour, salt, baking soda, baking powder, cinnamon and nutmeg. With your mixer on low, slowly add the flour and mix until combined.
Next, fold in oats and raisins until well combined.
Line a baking sheet with parchment paper and roll 1-½ tablespoons of dough into a ball and transfer to baking sheet.
Place cookies in preheated oven and bake for 12-14 minutes until golden and a toothpick runs through the cookie and comes out clean.
Remove cookies from the oven and transfer to a cooling rack.