Sift cornmeal, salt, baking soda, and baking powder into a mixing bowl. Stir in the beaten eggs. At this point, set a 9 x 10-inch baking pan in a 400°F oven with the lard and butter added. Pour the sour milk into the cornmeal batter and stir well.
Now remove the pan from the oven and tilt it all around to oil the whole surface of the pan. Pour off into the batter what fat remains. Mix well and pour the batter into the hot pan. Cornmeal batter must be poured into a sizzling hot pan, otherwise it will stick.
Bake at 400°F for 25 to 30 minutes. Remove and cut into squares. Serve hot.