Preheat oven to 350 ° F (180 ° C).
In a large bowl, combine olive oil (extra-virgin olive oil is more expensive, but lower grade olive oils are blended with other vegetable oils that may contain corn or soy), garlic and parsley. Heat the beef broth (it’s best to make your own, canned or condensed broths have added salt, sugars, and preservatives) or water until steaming and add to the olive oil mixture . Stir in barley flour and let cool until lukewarm — or cool enough to work with. Gradually blend in rye flour, adding enough to form a stiff dough.
Transfer to a floured (rye flour) surface and knead until smooth (about 3-5 minutes). Shape the dough into a ball, and roll to 1/4-inch (6 mm) thick. Use the cookie cutter of your choice (we prefer to make small bones) or cut into small squares. Transfer to ungreased baking sheets, spacing them about 1/4 inch (6 mm) apart. Gather up the scraps, roll out again, and cut additional biscuits.
Bake for 30 minutes. Remove from oven and turn over. Bake for an additional 30 minutes, or until golden brown on both sides. After you finish baking all batches of biscuits, turn off the oven, spread all the biscuits in one baking pan and set them in the oven to cool for a few hours or overnight. The extra time in the oven as it cools off helps make the treats crunchier.
Makes several dozen small treats that keep and freeze well.