1Heat oven to 350°F. In ungreased 8-inch square pan, mix flour, 1 cup brown sugar, the allspice and baking soda with fork. Stir in all remaining cake ingredients until blended.
2Bake 35 to 40 minutes or until toothpick inserted in center comes out clean.
3In 1 1/2-quart saucepan, heat all sauce ingredients to rolling boil over high heat, stirring constantly; reduce heat slightly. Boil 3 minutes, stirring frequently. (Watch carefully; mixture burns easily.) Store sauce in refrigerator.