In a very large mixing bowl, combine the water and yeast. Let stand to dissolve for 5 minutes.
Add the milk, butter, salt, sugar and flour to the yeast mixture and beat until smooth and blended. Cover the bowl and let stand overnight at room temperature.
Heat waffle iron.
Stir eggs and baking soda mixture into waffle batter, mixing well
Pour batter from cup or ladle onto center of hot waffle iron. Bake about 5 minutes or until steaming stops. Remove waffle carefully.
Makes 6 to 8 servings.