In a small saucepan, melt the stick of butter over medium heat until nut-brown in color, about 8-10 minutes.
Remove the pan from the heat and pour the butter into a bowl, leaving any burned sediments behind. Allow to cool slightly
Preheat the oven to 325 degrees F. In a medium mixing bowl, whisk together the graham cracker crumbs, pecans, brown sugar, and a pinch of salt until incorporated.
Pour in the brown butter and stir until combined. Press the mixture into the bottom and 1 ½ inches up the sides of a well-greased 9-inch springform pan.
Bake crust for 8 to 10 minutes or until lightly golden brown.
In a stand mixer with a paddle attachment, beat the cream cheese, granulated sugar, vanilla, and bourbon until smooth and combined.
Add the eggs, one at a time, beating until blended after each addition.
Add the pumpkin puree and lemon juice and mix until blended. Pour the prepared batter into the crust.
Bake at 325 F for 1 hour and 10 minutes or until almost set.
Turn off the oven and allow the cheesecake to stand in the oven (with the door closed!) for 15 minutes.
Remove the cheesecake from the oven, and gently run a knife around the outer edge of the cheesecake to loosen it from the sides of the pan.
Allow to cool completely on a wire rack. Cover and chill for 8 or 24 hours.
Preheat the oven to 250 F.
In a small bowl, mix together the sugars, cinnamon, salt, and nutmeg.
In a separate mixing bowl, whisk the egg whites, vanilla, and bourbon until frothy.
Toss the pecans in the egg white mixture until coated. Then mix in the sugar mixture until evenly coated.
Spread the pecans onto a baking sheet or a 9-inch cast iron skillet. Bake for 1 hour, stirring every 15 minutes until the pecans are evenly browned.
Allow to cool before garnishing on cheesecake.