Preheat oven to 350 degrees F. Place carrots in a large mixing bowl. Using a potato masher, mash carrots until only small pieces remain. Add brown sugar, oil and egg; mix well.
Add flour, oats, baking powder, cinnamon and salt. Mix with a wooden spoon just until dry ingredients are moistened. Fold in cranberries.
Spoon batter into 12 paper-lined medium muffin cups. Top with pecans. Bake 25 minutes or until wooden pick inserted in center comes out clean. Let cool 10 minutes before removing from pan. Muffins may be frozen for up to 3 months.