Preheat oven to 350ºF. Grease 9x13 baking pan and set aside.
With a stand mixer or in a bowl with hand- held mixer, beat butter (or non-dairy substitute) on medium speed until smooth and creamy. Add both sugars and beat until very well incorporated.
Add eggs, one at a time, then beat in vanilla.
Reduce speed to low and mix in baking powder, baking soda, and salt. Carefully add in flour and mix only until incorporated. Do not over mix.
Using a spoon or rubber spatula, stir in chocolate chips and nuts.
Pour batter into greased pan and smooth with spatula or back or spoon to evenly distribute.
Bake for 40-45 minutes or until a toothpick inserted into the center of the blondies comes out clean. If the toothpick comes out covered in chocolate try again in another spot. The blondies should be a golden, honey brown color on top.
Cool, cut into bars, and enjoy. Yum!