Preheat oven to 350° F.
Place refrigerated butter in the microwave for 30 seconds. (Tip: I like to keep the paper on it with the seal facing up, then I can pick it up with my fingers and slide it in the mixer easily, scraping the paper along the mixing paddles.)
Using a mixer, cream the butter and sugars until mixture is fully incorporated. Scrape down the sides as needed.
Add in the eggs (both at the same time is fine). Beat very well, until the color changes to a light beige and batter looks almost frothy (about 2 minutes on medium to medium-high speed). Again, scrape down the sides and mixing paddles as needed throughout mixing process.
Add the baking soda, salt and vanilla. Mix well.
Add in the flour. Mix just enough to be fully incorporated. Do not over-beat. (Important tip: Sometimes the amount of flour needs to be adjusted. It could be anywhere from just over 2 1/4 c flour to almost 2 3/4 c flour, but 2 1/2 c is most common. I like to add the flour slowly, first one cup, then the second cup on stir, then each quarter by itself while watching closely. The dough should not really stick to your fingers if you touch it when you are finished. A little sticking to the fingers is normal after you have scooped several onto the baking sheet. If your cookies are flat, you need more flour.).
By hand, stir in the chocolate chips.
Place cookie dough balls onto an ungreased baking sheet. (Tip: I use non-stick baking sheets. You can also use silpat. Dough balls do not need to be perfectly shaped but turns out fine if you do roll them in your hand.)
Bake for about 8 to 8 1/2 minutes or until peaks are lightly golden brown. This might take slightly longer if you crowded the baking sheet. Remove from baking sheet promptly and place onto cooling rack or a plate.