How to keep edible cookie dough soft after refrigerated?
Since most recipes use butter, I'm going to guess that's what you're using.

Think about butter in the fridge... what's it like? It's hard. Stiff.

Well, that's why your dough is getting hard. So, you have a couple of solutions.


Replace the butter with a fat that's softer when cold instead of using butter. Perhaps coconut oil?
Portion the dough before you put it into the fridge and let your portion warm back up to room temperature before eating it.


For me, I'd go with option two because I'd be worried about the texture when the cookies were warm, which would be much softer than they are currently, and I'd be worried about changing the flavor. If you're using the dough in something really cold - like ice cream - then option 1 would probably be fine for your needs.