1. Position racks in the center and top third of the oven and preheat to 350°F.
2. In a medium saucepan, bring the honey and butter to a boil over medium heat, stirring to melt the butter. Transfer to a large bowl and cool to room temperature. (Place the saucepan in a large bowl of ice water to speed up the process if you wish.) Add the eggs and mix well.
3. In a large bowl, sift the flour, granulated sugar, cinnamon, anise, nutmeg, pepper, baking powder, baking soda, cloves, and salt together. In three additions, stir the dry ingredients into the honey mixture, adding the candied citron with the last addition of flour. Stir in the rum to make a stiff dough.
4. Using a level tablespoon for each, roll the dough into 1-inch balls. Place the balls about 1 inch apart on cookie sheets lined with nonstick baking pads.
5. Bake, switching the position of the cookie sheets from top to bottom and back to front halfway through baking, until the cookies are lightly browned and feel firm when pressed with a finger, about 20 minutes. Cool for 5 minutes on the cookie sheets.
6. To make the icing, mix together the confectioners’ sugar with enough water in a small bowl until the glaze is the thickness of heavy cream. One at a time, holding the cookies upside down, dip the tops of the cookies into the glaze. Let the excess glaze drip off, then place the cookies right side up on wire racks to cool completely. (The cookies can be stored for up to 2 weeks in airtight containers at room temperature.) If possible, age the cookies for 2 days before serving.