In a large, heavy pan, melt one stick of butter over medium heat until it browns and smells nutty. The butter will foam, sizzle and look angry. Swirl the pan constantly until butter is brown. This takes about 5 minutes. Small bits of brown butter granules will appear on the bottom of your skillet. Do not burn. After the butter has turned brown, pour into a heat proof bowl to cool. Set aside and cool for up to 30 minutes.
Add second stick of softened butter and the brown sugar to a large bowl or a stand mixer fitted with the paddle attachment. Beat at medium speed until sugar has dissolved into the butter and is no longer grainy- about 5 minutes. The sugar mixture will be smooth. Reduce speed of your mixer and add in vanilla, molasses, coffee and beat until well blended. Add cooled browned butter and remaining white sugar. Scrape down the bowl of the mixer.
Reduce speed to low and add eggs. Beat until combined. Add in flour, salt and baking powder slowly. Fold in chips and pecans.
Cover cookie dough and chill in fridge for at least 2 hours or up to 24 hours.
Pre-heat oven to 350 degrees.
Line an insulated cookie sheet parchment paper.
Scoop dough with a small ice cream scoop (about 2 tablespoons per cookie) and set on baking sheets. Leave about 2-3 inches between cookies. Bake for 12 minutes. Remove and let cool on baking sheet for 1-2 minutes then set cookies onto a wire rack to cook completely. Recipe makes about 3 dozen cookies.