Preheat oven to 350 degrees F.
Line baking sheets with parchment paper. Set aside.
In a large bowl cream the butter and both sugars together. You want the mixture to be creamy.
Add the eggs and vanilla extract to the bowl. Mix until combined.
Add the flour, baking soda and salt, mix until well combined.
Next, add the oats and mix until incorporated.
Add the raisins and fold in until evenly distributed. Do not use a stand mixer or hand mixer for this step.
Use a tablespoon or cookie scoop to drop dough onto the lined baking sheets.
Place the cookies in the preheated oven and bake for 10 to 12 minutes, or until the edges are golden.
Remove the cookies from the oven. Allow to cool for a couple of minutes, then transfer the cookies to a cooling rack.
Cool completely before storing.