Preheat the oven to 350 degrees and lightly grease a cookie sheet.
Cream together the bacon grease, butter, sugar. Add the egg, buttermilk and vanilla and beat until fluffy.
Mix together the flour, baking powder, baking soda, cinnamon, salt and cayenne and add to butter, sugar and egg mixture. Beat until well incorporated and then stir in the chocolate chips and nuts.
Roll dough into walnut-sized balls, place on parchment-sheet lined cookie sheets and bake for 17 minutes.
Notes
You can swap out the pecans for 1/2 cup peanut butter. Also, if you want a flatter cookie, press down on the dough ball with a fork before baking.