Lay the dates on the pan ensuring they do not overlap.
Bake for 10-15 minutes or until the dates are hard as a rock.
Remove from oven and allow to cool.
Using a very, VERY powerful food processor or spice/coffee grinder (make sure it’s a grinder that’s only used for foods), add a handful of the dates to the grinder and process until a powder forms.
Add in a pinch or two corn starch to each batch and process for a few seconds. This will help the sugar to not clump.
Continue with the rest of the dates.
Store the sugar in an air tight container.
Notes
In baking I substitute date sugar as such:
1 cup of brown sugar = 1/2 cup date sugar
1 cup white sugar – 2/3 cup date sugar