In a bowl mix well oat flour, flakes, baking powder and spices.
Pour in the tahini and stir the mixture well with a spoon until smooth.
Making Filling
Remove the pits from the dates and chop them finely.
Place the dates and salt in a saucepan, add water and simmer over medium heat until the dates are soft and can be mashed with a spoon into a smooth paste.
Mash the dates with a spoon until you get a smooth paste.
Assembling the Pie
Prepare a baking dish by lining it with parchment paper.
Place 2/3 of the dough on the bottom of the dish.
Spread the date paste evenly over the dough layer.
Place metal cookie cutters on top of the date layer. Spoon the remaining 1/3 of the dough between the cutters. Pack tightly, leaving no gaps between the cutters and the dough. This will create a beautiful pattern on top of the pie. Do not remove cutters.
Bake the pie for 25 minutes.
Remove cutters carefully. Cool completely before slicing. Store the pie in a container with a tight-fitting lid.