Line an 8x8 inch square baking pan with foil or a foil/parchment liner. Grease any additional exposed sections of the pan with butter. Add sifted confectioners' sugar and bourbon to the bowl of your stand mixer.
Begin by making brown butter. Add butter to a medium sized sauce pot and cook over medium high heat. Allow to melt and then bubble while frequently stirring to scrape any of the wonderful brown bits off the bottom of the pan. You know when you're done when you see little brown specs and it smells nutty like caramel. Do not overcook. Once done, turn off heat.
Add brown sugar and evaporated milk to the browned butter. Cook mixture over medium heat about 2 minutes, stirring constantly, until sugar is dissolved. Then, heat to full rolling boil and stir 1 minute. Remove from heat. Immediately add to the stand mixer bowl with the powdered sugar.
Using the paddle attachment, beat on low speed 1 minute to combine. Increase speed to medium and beat 6-10 minutes or until mixture begins to hold its shape and is warm to the touch. Quickly stir in the raw pecan pieces.
Transfer fudge to prepared pan. Set candied pecan halves on top in rows so that once cut, each piece will have a pecan half on top.
Allow to set. Mine set perfectly well in a cool house after about 4 hours. You can also refrigerate for 2 hours to help firm up, if needed.
Lift the fudge out of the pan and cut into pieces. Store in airtight container.