Pre-heat oven to 350 degrees Fahrenheit and prepare 9×13 pan with cooking spray (or butter) and flour. Whisk together flour, baking soda, and salt and then set aside. In a larger bowl, mix butter and sugar together until well blended.
Add egg, egg white, and vanilla and continue to mix until incorporated. Gradually add flour mixture and combine until well incorporated.
Fold butterscotch and chocolate chips into the batter and spread dough evenly into the prepared pan.
Bake the blondies for 25 minutes or until golden brown. Let the blondies cool for approximately 30 minutes before slicing/serving.