Preheat oven to 425degreesF.Put first 5 ingredients in mixing bowl. (If it makes you feel better, go ahead and mix the dry ingredients, whisk the eggs into the buttermilk, then combine dry/wet ingredients).Mix with large spoon or whisk.Put bacon grease in well-seasoned 10-inch cast iron skillet over medium to high heat.Just as the bacon grease is about to start smoking, pour it into the other ingredients, stirring as you pour (if you can manage it). Leave enough in the skillet to coat the bottom and sides.Pour entire mixture into the skillet.Place skillet on middle rack of oven; bake until cornbread is springy in the middle, browned and pulling away from the skillet on the sides (about 15-20 minutes).Remove from oven and invert skillet over serving plate. If cornbread does not drop easily, you may need to run an icing spatula or even a flexible metal egg-turner around/under it so it comes loose.Recipe halves well, just remember you can't cut the bacon grease by half because you still need to coat the skillet.Serve hot, with plenty of butter. Or margarine, if you insist.