Mix flour with baking soda. Combine butter, the sugars and vanilla in large mixer bowl; beat until smooth and creamy. Beat in eggs, one at a time. Gradually add flour mixture, then stir in chips. (Batter will be stiff.)
Drop by rounded teaspoon about 2 inches apart, onto ungreased baking sheet. Bake at 375 degrees for 8 to 10 minutes.