Line a deep baking tin approx size 34cm x 24cm with non stick baking paper.
Pre-heat the oven to 170C.
First make the filling by placing the dates, orange juice and cinnamon in a saucepan and simmering slowly, stirring from time to time until they are soft, sticky but spreadable as a thick paste.
Place the flour, oats, sugar and fat into a deep mixing bowl and rub together to form a soft crumbly texture.
Press half the oat mixture into the tin firmly to form a base.
Spread the date mixture across the top of the oat base, levelling it as you go.
Sprinkle the remaining oat crumble mix across to the top of the dates, scattering it evenly and pressing gently.
Bake in the centre of the oven for approx 40 mins, until golden brown on top.
Leave in the tin until cold and then cut into slices.