In a bowl, mash the banana.
Add vanilla, sugar and milk, mix and set aside.
In another bowl, mix flour, baking powder and carob.
Place the milk mixture over the flour and mix until blended.
Add nuts and chocolate chips and mix.
Place in muffin tins.
Bake in a very low temperature oven for ½ hour or until a toothpick to prick comes out clean.
Cool on rack.
Sprinkle with powdered sugar and serve.