Preheat oven to 350 degrees, with rack in center. Generously butter a 12-by-17-inch rimmed baking sheet; set aside. In a medium bowl, whisk together flour, baking soda, and salt; set aside.
In the bowl of an electric mixer fitted with the paddle attachment, cream butter and sugars on medium speed until light and fluffy, about 2 minutes. Add eggs and vanilla; mix until well combined. Add flour mixture; beat on low speed until just combined. Beat in chocolate chips.
Spread dough on prepared baking sheet. Bake, rotating sheet halfway through, until edges are brown and top is golden, 40 to 45 minutes. Transfer to a wire rack; let cool completely on baking sheet. Use a serrated knife to cut into 1 1/2-by-4-inch bars.