Carrot and Banana Bran Muffins

Name: Carrot and Banana Bran Muffins
Yield: Makes 12 muffins or 24 mini muffins.
Ingredients: 1 egg, lightly whisked; 2 bananas, mashed; 1/2 cup Greek yoghurt; 5 Tbsp maple syrup; 1 tsp vanilla; 1 carrot, grated; 3/4 cup wholegrain oats; 1 tsp baking soda; 1 1/2 tsp cinnamon; 1/2 tsp ground ginger; 1/4 tsp nutmeg; 1/4 tsp salt; 1 1/4 cup wholemeal flour; 1/3 cup walnuts; Icing; 120g lite cream cheese; 40g icing sugar; 1/2 tsp vanilla