In a small bowl combine the dates and baking soda. Pour enough boiling water over the dates to just cover them.
Cream ¼ cup plus 1 tablespoon of the butter with the white sugar until light. Beat in the eggs and mix well to combine.
Add the flour and date mixture (including water) to the egg mixture and fold to combine. Pour the batter into one 8 inch round baking pan.
Bake at 175°C for 30 to 40 minutes. Let cool, slice and serve with warm caramel sauce.
CARAMEL SAUCE:
In a small saucepan combine the brown sugar, evaporated milk, vanilla and ¼ cup plus 1 tablespoon of butter. Cook over medium heat and bring to boil. Turn heat down and simmer for 5 minutes, stirring occasionally.