Wash your hands before starting. Dust how many ever cookie sheets will fit in your oven and place them next to a table where you’ll do the work. Preheat the oven to 350 degrees.
With hands mix flour and water in a large bowl until the gooey mass doesn’t
stick to your hands (have a separate bowl of flour handy to add for this
purpose). Do not coat your hands with Crisco to prevent sticking as this
causes problems with the final product. Just deal with it.
Dust flour on a table surface and take the dough and knead it there until
leathery stiff (and your wrists begin to ache). Do the next parts steadily and without letup to prevent rising. Form dough into a rounded shape.
With rolling pin roll it out to 1/2-inch thick. Cut into 3-inch squares and place on the cookie sheets. With 3-tined fork, make hole patterns on one side. (I use a hard tack cutter with nails already in pattern – some tin sutlers
sell these – ask around the membership because maybe someone has one)
Place sheets in oven and bake each side of hard tack for 30 minutes at 350
degrees. Stack finished tack into a box and let set up for one day at which time they will gain the consistency of a brick.
Some people add a little salt to the dough but there is no historical
evidence for this. The salt makes it even harder but also attracts
moisture which will eventually ruin tack stored for a few months (and a lot
of mine is stored for a year).