Step 1Stir together flour, brown sugar, baking powder, cinnamon, salt, ginger and allspice in large mixing bowl.
Step 2Cut in shortening with 2 knives or dough cutter until crumbly.
Step 3Add sweet potatoes and mix well with wooden spoon. Add cream and pecans and stir just until moistened.
Step 4Turn dough out onto a lightly floured surface. Roll out dough to 1 1/2 inches thick. Cut out biscuits with a floured 2-inch biscuit cutter. Place biscuits 1 inch apart on ungreased baking sheets.
Step 5Bake at 350 degrees until golden brown, 25 to 30 minutes. Serve warm or cool on wire rack to room temperature.