As you ask specifically for biscuits/hard tack, I have a couple of recipes that I saved from when, I think, they were covered here. It could have been from somewhere else but I'm pretty sure we can thank either Jonas or Mort for them:
Hardtack & Johnnie Cake
Here's survival food that goes back many years. The recipes are from the American Civil War (or more properly, The War of Northern Aggression). The South didn't have a lot of wheat, but did have plenty of corn, hence the Johnnie Cake (for "Johnnie Reb"). Hardtack has a lifespan of several years (just ask the crew of HMS Bounty!).
Army Hardtack Recipe
4 cups flour (preferably whole wheat)
4 teaspoons salt
Water (about 2 cups)
Pre-heat oven to 375° F
Makes about 10 pieces
Mix the flour and salt together in a bowl. Add just enough water (less than two cups) so that the mixture will stick together, producing a dough that won’t stick to hands, rolling pin or pan. Mix the dough by hand. Roll the dough out, shaping it roughly into a rectangle. Cut into the dough into squares about 3 x 3 inches and ½ inch thick.
After cutting the squares, press a pattern of four rows of four holes into each square, using a nail or other such object. Do not punch through the dough. The appearance you want is similar to that of a modern saltine cracker. Turn each square over and do the same thing to the other side.
Place the squares on an ungreased cookie sheet in the oven and bake for 30 minutes at 350°F. Turn each piece over and bake for another 30 minutes. The crackers should be slightly brown on both sides.
The fresh crackers are easily broken but as they dry, they harden and assume the consistency of fired brick.
Union Hardtack Recipe
2 cups of flour
1/2 to 3/4 cup water
1 tablespoon of shortening or vegetable fat
6 pinches of salt
Mix the ingredients together into a stiff batter, knead several times, and spread the dough out flat to a thickness of 1/2 inch on a non-greased cookie sheet. Bake for one-half an hour at 400°F. Remove from oven, cut dough into 3-inch squares, and punch four rows of holes, four holes per row into the dough. Turn dough over, return to the oven and bake another one-half hour. Turn oven off and leave the door closed. Leave the hardtack in the oven until cool. Remove and enjoy!
Confederate Johnnie Cake Recipe
2 cups of cornmeal
2/3 cup of milk
2 tablespoons vegetable oil
2 teaspoon baking soda
1/2 teaspoon of salt
Mix ingredients into a stiff batter and form eight biscuit-sized "dodgers". Bake on a lightly greased sheet at 350°F for twenty to twenty five minutes or until brown.
Or, spoon the batter into hot cooking oil in a frying pan over a low flame. Remove the corn dodgers and let cool on a paper towel, spread with a little butter or molasses, and you have a real southern treat!
Pirate’s Hard Tack Recipe
2 cups of flour
1/2 to 3/4 cup water
6 pinches of salt
1 tablespoon of shortening (optional)
Mix all the ingredients into a batter and press onto a cookie sheet to a thickness of ½ inch.
Bake in a preheated oven at 400°F (205°C) for one hour.
Remove from oven, cut dough into 3-inch squares, and punch four rows of holes, four holes per row into the dough (a fork works nicely).
Flip the crackers and return to the oven for another half hour.
Some recipes also recommend a second baking at 250°F (120°C) to thoroughly dry out the bread.
RE: Hardtack & Johnnie Cake
I have made many batches of hard tack over the years. Most with just flour and water. I double bake mine just to insure all the moisture is baked out.
I have seen hard tack in museums that was baked in the american CW and from appearances it is still fit to eat, if any of it could be considered fit to eat.
My kids also had a favorite HT recipe which substituted honey for the water and a final dusting of powdered sugar. That never lasted long.
And back to Grumpy...
Not sure about how long these will stay edible (if they are at all!
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) but I would think that sealed in airtight containers, it could be a very long time. Time for baking and experimenting maybe?