Preheat the oven to 350 F. In a medium bowl, whisk together flour, oats, salt, and baking soda. In a large bowl, combine butter with peanut butter and both sugars until fluffy. Add in egg and vanilla extract, and mix until smooth.
Add in the flour mixture until it is fully combined. Fold in the chocolate chips. Evenly press the cookie dough into a greased 8-inch square baking dish. Bake for 20-25 minutes.