First, brown the butter. Place butter in a small saucepan over medium-high heat. Cook and stir until golden specks form, and the butter gives off a nutty smell.
Pour the butter into a large mixing bowl (scraping the brown bits from the bottom of the saucepan) and set aside to cool. To help it cool faster, you can refrigerate the brown butter for 15-20 minutes.
Preheat oven to 350℉ and line a large baking sheet with parchment paper. Set aside.
In a medium-sized bowl, combine the flour, baking soda, salt, and cinnamon. Set aside.
Once the brown butter has cooled, add the brown sugar and granulated sugar to the bowl. Beat on high speed for 1 minute.
Add the eggs and vanilla extract and beat until fully combined.
Add the dry ingredients and mix to combine. Use a rubber spatula to scrape the sides and bottom of the bowl as needed.
Stir in the chocolate chips and pecans until evenly mixed into the dough.
Using a 2 tablespoon cookie scoop, place your cookie dough balls 2 inches apart on the prepared cookie sheet. If desired, top the dough with additional chocolate chips and pecans.
Bake for 9-10 minutes until the edges are golden and the middle is still soft and slightly puffed. Remove from oven.
Allow cookies to cool on the cookie sheet for about 2 minutes, then transfer to a wire rack to cool completely.