Whip the creamed cheese, gradually adding the sugar, until light and fluffy and sugar well combined. Add egg and banana and combine until well mixed. Add carrot and gently fold through flour (don't over mix or beat as batter will become tough). If batter is too thick add a small amount of milk. Place in a greesed muffin tray and bake at 180 degrees for 20 - 25 mins, or until lightly browned and firm to firm to the touch. Baking times will vary depending on size of muffins.