Place the 1 tablespoon butter in a 2- or 2-1/2-quart nonmetal deep baking dish and place dish in oven. Set oven temperature to 400'F.
In a saucepan combine cornmeal, salt, sugar, and boiling water. Cook, stirring over low heat, until thick and smooth. Remove from heat and slowly add milk, stirring. Add eggs one at a time, beating well after each addition. Stir in melted butter and baking powder and beat until batter is well blended.
Remove heated baking dish from oven and rotate to distribute butter evenly over bottom and sides. Pour in batter and bake in preheated oven until firm, about 45 minutes.
Serve hot from the baking dish.