Put butter in a small pot. Heat over medium heat. 1/2 cup unsalted butter
Allow the butter to continue cooking, stirring often as it melts, then bubbles and foams. Scrape the sides and watch for it to get a nutty smell, and start to turn to an amber color. Remove from heat.
Pour the butter into a separate bowl and let it set to cool to room temperature for about 30-45 minutes.
Preheat the oven to 350 degrees Fahrenheit. Line a baking sheet with parchment paper, or a silicone liner.
In a large bowl, whisk together the brown butter, and sugars until smooth. 1 1/3 cup brown sugar, 1/2 cup granulated sugar
Add in the banana and vanilla extract and stir until combined. 2 ripe bananas, 1 TBS vanilla extract
In another bowl combine the flour, cornstarch, baking soda, and salt. 3 cups all purpose flour, 2 TBS cornstarch, 1 tsp baking soda, 1/2 tsp salt
Gently stir 1 cup of the flour mixture in at a time, just until it's all mixed in.
Gently fold the chopped chocolate bar, and pecans, evenly into the cookie dough, until just mixed in. (Reserve about 1/4 cup of each to add to top of the cookie balls, if desired) 8 oz chocolate bar, 2/3 cup pecans
Using a large cookie scoop, scoop up about 3 TBS of dough and roll the cookie dough into balls. Place 9 to 12 cookies on a sheet, about 2 inches apart. Top each ball with a couple pieces of chocolate and pecan pieces.
Bake the cookies for about 10 minutes, or until the cookies are just golden brown.
Remove the cookies from the oven and let them cool for 10 minutes on the pan, before transferring them to a cooling rack. Let them cool more as desired.
Enjoy.
The cookies can be stored in an airtight container, or ziptop bag, at room temperature for up to 3 days.