Preheat oven to 350F. In a large bowl combine butter and sugars. Beat on low with an electric hand mixer or in a bowl of a stand mixer until smooth and creamy. Add egg vanilla. Mix on low until combined. Set aside.
In a separate large bowl, combine dry ingredients. Whisk to combine and add to wet ingredients gradually. Add ½ or 1 cup at a time, beat on low until combined, and then continue with the next batch.
Mix until ingredients are almost combined, a few lumps here and there are fine.
Stir in the chocolate chips. Freeze the batter for 30 minutes to an hour or at least 1 hour in the fridge (even better 2-3 hours). It is important to chill the batter between the batches too.
The batter will resemble playdough and should not be sticky after chilling. Scoop 2 tablespoonfuls of batter, rolling it into about 2 inch balls.
Arrange the cookie balls on a baking sheet lined with parchment paper at least 2 inches apart. Don’t press down!
Bake for 10-12 minutes (the time varies due to different ovens).
The cookies will have a soft center inside. Once they cool down they will set well and the texture inside remains soft, chewy and buttery.
Let the cookies stand in the pan for 5-10 minutes before transferring to a wire rack.