Combine the cornmeal and salt. Slowly stir in the boiling water and melted butter. Cover and let stand for 10 minutes. Stir in the buttermilk and egg. Combine the flour and baking soda and stir quickly into the batter. The batter will be very thin.
Bake on a well-greased griddle over medium heat, using a tablespoon of b for griddle cake. Stir the batter often and keep the griddle well greased. When golden brown underneath, turn to brown the other side. Turn only once.
Serve with warmed maple syrup.