Preheat oven to 350°F (175°C). Grease and flour a 9x13 inch baking pan.
In a large bowl, cream together the butter and sugar until light and fluffy. Beat in eggs one at a time, then stir in the vanilla.
In a separate bowl, whisk together the flour, baking soda, and salt. Gradually add to the creamed mixture and mix until just combined. Stir in chocolate chips.
Spread batter evenly into the prepared pan. Bake for 25-30 minutes, or until golden brown.
Let cool completely before cutting into bars.
Notes
Store leftover bars in an airtight container at room temperature for up to 3 days.