In a medium bowl, whisk together the flour, baking soda, cinnamon, allspice, pepper and salt. In a stand mixer with the paddle attachment, beat the butter and brown sugar on medium until light and fluffy, about 5 minutes. Add the eggs one at a time, mixing well after each and scraping down the bowl as needed. Add the flour mixture in 2 additions, mixing on low after each until only a few streaks of flour remain. Fold in the cranberries with a rubber spatula.