Salted Peanut Butter and Chocolate Blondies

I followed the recipe exactly. I did not leave out or substitute any ingredients. When they came out of the oven, they tasted just "okay." They were a little bit dense, but definitely still edible. I thought the sea salt gave it a nice flavor. I sliced them as instructed and then covered them with plastic wrap and went to bed. The next morning, I went to re-package them into a travel container to take to an event. They were hard as rocks. You could not cut them with a knife, let alone bit into one of them. I had to throw away the entire batch. Its such a shame. I know that not every recipe will be perfect, but I was disappointed that not only did I waste money on ingredients, but also because I did not have a homemade dessert to bring to the event.