In a medium bowl, whisk together the flour, baking soda, and salt until evenly combined. Set aside.
In a large bowl, beat the softened butter, granulated sugar, and brown sugar for 2 to 3 minutes until pale and fluffy.
Reduce mixer speed. Add the vanilla extract and egg, then mix until smooth and fully blended. Scrape down the bowl as needed.
Add the dry ingredients to the butter mixture. Mix just until a few streaks of flour remain.
Stir in the rolled oats and chocolate chips until evenly distributed and the dough comes together.
Cover the bowl and chill the dough for at least 1 hour or up to overnight for thicker cookies and deeper flavor.
Preheat the oven to 375°F (190°C). Line baking sheets with parchment paper.
Scoop about 2 tablespoons of dough per cookie and place on the baking sheets, leaving 2 inches of space between each.
Bake for 8 to 10 minutes until the edges are golden and the centers still look slightly soft.
Let cookies rest on the baking sheet for 1 to 2 minutes, then transfer to a wire rack to cool completely or enjoy warm.