In a saucepan, combine brown sugar, water, raisins, shortening, nutmeg and cinnamon. Bring to a boil, and continue boiling for 3 minutes. Remove from heat and allow to cool.
Preheat oven to 350 degrees F (175 degrees C). Grease and flour a 9 inch square pan. Sift together flour and baking powder.
In a large bowl, combine the raisin mixture with the flour mixture. Pour into prepared pan.
Bake for 45 minutes in the preheated oven, or until a toothpick inserted into the cake comes out clean.
