Preheat the oven to 350°F and line baking sheets with parchment paper.

Mix the flour, baking soda, and salt in a medium bowl. Set aside.

In a large bowl, cream the softened butter, granulated sugar, and brown sugar until light and fluffy.

Beat in the egg and vanilla extract until well combined.

Combine wet and dry: Gradually add the dry ingredients to the butter mixture, mixing at low speed until combined. Do not overmix.

Stir in the rolled oats and chocolate chips.

Gently fold in the sour cream until just incorporated.

Drop rounded tablespoons of dough onto the prepared baking sheets using a cookie scoop, leaving some space between each cookie.

Bake for 12-14 minutes or until the edges are golden brown and the centers are set.

Let the cookies cool on the baking sheets for a few minutes before transferring them to a wire rack to cool completely.