In the bowl of a food processor, combine all ingredients and pulse until the mixture looks like rough crumbs. Slowly add the water 1 teaspoon at a time, pulsing to blend until the mixture comes together into a dough when pressed together.
Turn the dough out onto a large piece of plastic wrap, gather into a ball and knead once or twice to bring the dough together. Flatten the dough into a square and wrap with plastic. Refrigerate the dough until firm, at least 20 minutes or up to 2 days. Or, freeze for up to a month to bake later.
Heat oven to 350ºF. Line a baking sheet with parchment paper. On a floured surface, roll out a quarter of the dough to about 1/8-inch thick. Cut dough into squares about 1-inch by 1-inch. Make a small hole in the center of each cracker with a skewer or chop stick. Sprinkle with a pinch of additional salt if desired. Bake 10 to 14 minutes or until the crackers are lightly browned. Cool and repeat with remaining dough. Store in an airtight container for up to 4 days.