Preheat oven to 350 degrees. Line baking sheet with parchment or silicone baking mat and set aside. Place butter into small pot over medium heat. After butter has melted, start swirling pot gently until it starts to brown and become fragrant. Once the butter is a golden amber color, take off the heat and pour into the bowl of a mixer. Pour in sugar and brown sugar. Stir. Mix in egg and vanilla. Scrape sides and stir again. Pour in all dry ingredients and stir slowly. Scrape sides and mix again briefly. Stir in chocolate chunks and stir by hand. Scoop by the teaspoon into pans and bake 7-8 minutes or until lightly golden around the edges. Remove from oven, cool 5 minutes and transfer to cooling rack. Serve.