Preheat the oven to 375F

In the bowl mix 3 cups of flour with the salt

Add 1 cup of tap water and stir until it becomes too difficult

Knead dough in bowl with hand, adding more flour to make it very dry. Press, pull, and roll the dough into a rectangle that can be divided into 3-inch squares of 1/2-inch thickness. Use a table knife to cut dough into squares

Holding each square in hand, punch 16 holes through it with an eight-penny nail, being careful not to hurt yourself. Place dough squares on ungreased baking sheets and bake for 30 minutes, until crisp and lightly browned

Cool before storing in a closed container

Makes 16 pieces.