Preheat the oven to 350 degrees F, then grease & line (with parchment) a 7"x11" cake pan.
Combine the dates & orange juice in a saucepan & bring to a boil before turning the heat down to low ~ Cover the saucepan & simmer gently for 5 minutes to soften the dates.
Remove from the heat & mash the date mixture until smooth, then set aside to cool.
In a mixing bowl, beat together the butter & sugar, then stir in the oats & flour to form a crumbly mixture.
Press half of this mixture into the base of the prepared pan to form a smooth base, then use a fork to prick the base all over.
Bake for 10-12 minutes or until lightly golden.
Spread the date paste over the cooked base & sprinkle the remaining crumbly mixture over that as a topping.
Return to the oven & bake for another 30 minutes or until lightly golden.
Remove from the oven, cut into 12 bars & allow to cool in the pan on a wire rack.
Great served either warm or cold.