In a saucepan combine the dates, 1/2 cup of sugar, 2 tablespoons of flour, and water. Bring to a boil, and cook until thickened, about 10 minutes. Remove from heat, and set aside to cool.
Preheat the oven to 325 degrees F (165 degrees C). Grease a 9x13 inch baking dish.
In a medium bowl, cream together the shortening and brown sugar until smooth. Beat in the eggs one at a time, then stir in the vanilla. Dissolve the baking soda in hot water, then stir into the creamed mixture. Combine 1 3/4 cups of flour and salt; stir into the batter just until blended.
Spread half of the batter in the bottom of the prepared pan. Cover with a layer of orange slice candy, then spread the date mixture over the orange candy. Cover with the remaining batter.
Bake for 30 minutes in the preheated oven, or until golden brown. Cool, and cut into bars.