Preheat the oven to 375°F. Line two pans with parchment paper.
Beat butter, white sugar, and brown sugar together in a large bowl with an electric mixer or stand mixer until light and fluffy.
Add eggs one at a time, beating well after each addition. Beat in vanilla.
Stir together flour, baking soda, cinnamon, and salt in a separate bowl. Gradually add flour mixture to butter mixture and mix until blended.
Mix in oats and butterscotch chips until combined.
Form the dough into balls around 1 inch wide and place onto the prepared baking sheets 2 inches apart. Press the cookies down with a fork, or wet the bottom of a drinking glass and press the cookies into an even layer. This helps them spread out and cook evenly.
Bake in the preheated oven until the edges begin to brown, 8 to 10 minutes.
Remove and cool completely on baking sheets as they are delicate when hot.
Notes
These cookies bake better when pressed down with a fork or glass bottom.
You can also switch out the baking chips for any flavor that you enjoy!