Make the filling by mixing together dates, 1 cup water and 1/2 cup brown sugar. Cook until thick; cool before spreading. The filling should be prepared before beginning mixing the other ingredients.
Pre-heat oven 350 degrees. Cream butter, add sugar, flour, rolled oats, salt and soda. Divide mixture in two and spread half of it on the bottom of the baking pan. Place the date filling, given below, on top of this and spread the remaining half of the mixture on the filling. Bake in a moderate oven for 30 minutes. Cut when cool.