Add 1/2 cup (1 cube) of butter to a frying pan on medium heat. Let cook until butter is sizzling, about 5 minutes. Add chopped pecans and 1/4 cup brown sugar. Decrease heat to medium-low and let cook (stirring occasionally) while you assemble the rest of the cookie dough.
In a mixing bowl combine the remaining 1/2 cup of softened butter and the granulated sugar and remaining 2/3 cup brown sugar until creamy. Add in eggs and vanilla. In a separate bowl combine all of the dry ingredients except the chocolate chips. Add dry ingredients to mixing bowl in 3 parts, mixing as you go until it's all added.
Take the buttery-pecan mixture in the frying pan and pour it into the mixing bowl. Mix to combine. Dough will be very soft and more the consistency of muffin batter, rather than cookie dough. Put the entire mixing bowl in the freezer for 15 minutes to firm it back up.
Preheat oven to 350 degrees F.
After dough has chilled, attach bowl back to the mixer and add in chocolate chips. Scoop dough out in 1.5 TBSP portions onto a cookie sheet lined in parchment paper.
Bake cookies for 10 minutes, allowing them to sit an extra 2-3 minutes on the tray once they come out of the oven. Transfer to a cooling rack.