I Laid down thinking it was just going to be for a few minutes, then I woke up many hours later, But I realized that I forgot to bentch. Is there any Tikkun…Can I still eat a k’zayis & bentch?
The sleep is considered a hefsek, so that you cannot now continue to eat.
On the other hand, having slept for many hours (more than 72 min), the benching for your meal is doubtful, depending on whether you feel hungry. This is hard to gauge, because often one doesn’t feel hungry after sleeping, irrespective of the previous meal.
The best thing to do would be to wash, make a new hamotzi, eat a little, and then to bench, having in mind even the previous meal.