Ingredients

• 17.6 oz dark corn syrup
• 3 tablespoons water
• 0.35 oz potash
• 1 tablespoon rum
• 5.28 oz rock candy
• 3.52 oz  sugar
• 2.1 oz candied orange peel
• 2 teaspoons cinnamon
• 2 teaspoons aniseed, ground
• 2 teaspoons coriander, ground
• 1 pinch cloves, ground
• 21 oz flour
• Some dark syrup and water

Directions

1. In a saucepan over medium heat, stir together syrup and water until hot.
2. Remove from heat and cool slightly. Dissolve the potash in the rum. Break the rock candy into very small pieces.
3. Add all of the ingredients to a large mixing bowl and knead until dough forms. Wrap in plastic wrap and let dough rest for 5 days in a cool place.
4. Preheat oven to 350 F. Grease baking sheets. On a lightly floured board, roll dough out to 1/4 inch thick and cut out 1-inch by 2-inch rectangles.
5. Place cookies on prepared baking sheets, about 2 inches apart. Bake 15 minutes. Allow to cool for one minute on baking sheet and then remove to wire racks to cool completely.
6. Glaze the cookies with a mixture of one part syrup to one part water. When dry, store in tins at room temperature.
7. Potash is potassium carbonate, a chemical leavening which helps baked goods stay moist. It tastes really bad by itself, but when it’s baked into cookies the taste goes away.
8. You can buy it in little packets in German stores. If you can’t get any, substitute baking soda.