I have the nicest customers at the bookshop.
I told one of them about the food soldiers ate in colonial times. He's more interested in the Civil War, and had ordered some "authentic" hardtack. He promised to bring me a taste.
And he did!
He insisted I wait and eat it with strong coffee. The soldiers would have boiled their coffee and drank it with grounds in their cups.
A box costs quite a bit, so he gave me one of the large crackers. I took it home and divided it with my family.
We brewed some regular coffee, since that's all we had.
It tasted a lot like a saltine, maybe a little more flour-y. We all agreed that it would taste pretty good if you're a hungry soldier on the march, but we wouldn't want to eat it all the time.