Combine sutanas and water in a small bowl. Let soak for 15 minutes. Drain sultanas, discard water and set sultanas aside.
Preheat oven to 180 degrees C. Grease muffin pans or line with paper muffin liners.
In a large bowl sift together flour, baking powder, bicarbonate of soda, salt and cinnamon. In a separate bowl beat eggs, oil and brown sugar. Combine egg mixture and flour mixture. Mix until just moistened. Fold in carrots and drained sultanas. Spoon mixture into prepared muffin pans.
Bake in preheated oven for 20 to 30 minutes. If using icing, let the muffins cool for 30 minutes before applying.