Method
In a large mixing bowl, combine the flour, oats, baking powder, and cinnamon. In another bowl, blend the butter, egg, sugar, salt, and vanilla. Stir in the cranberries, apple, and raisins into the batter. Pour it into the muffin pan, filling ⅔ of each cup. Bake the muffins in a 400 °F preheated oven, until a toothpick inserted into the center of a muffin comes out clean. Let the muffins cool on a wire rack before serving.