Combine raisins and water in a small bowl. Let soak for 15 minutes. Drain raisins, discard water and set raisins aside.
Preheat oven to 350 degrees F (175 degrees C). Grease muffin cups or line with paper muffin liners.
In a large bowl, sift together flour, baking powder, baking soda, salt and cinnamon. In a separate bowl, combine eggs, oil and brown sugar; beat well. Combine egg mixture and flour mixture; mix just until moistened. Fold in carrots and drained raisins. Spoon into prepared muffin cups.
Bake in preheated oven for 20 to 30 minutes. Let cool for 30 minutes before frosting.