Mix the dates and a little bit of water in the food processor to a thick paste. Add the cinnamon and cardamom and mix well. In a pie plate or similar flat dish, spread one cup of ground almonds into a layer. Sprinkle a light layer of confectioner's sugar over the almonds. Spread the date mixture over the top, being careful not to disturb the almond layer underneath. Sprinkle another light layer of confectioner's sugar over the date paste. Top with the rest of the ground almonds, pressing lightly into the pan. Keep in the refrigerator to prevent it from spoiling and to keep it from being too sticky. Cut into small pieces.