Preheat oven to 375 degrees F.
Grease 12 muffin cups or line with paper cups.
In a large mixing bowl, use a fork to stir the flour with the sugar, baking powder, cinnamon, nutmeg and salt.
Make a well in the centre.
In a small bowl, whisk the milk with the egg and vanilla.
Whisk in the butter.
Peel the apple, if you wish, and coarsely chop.
Pour the milk mixture into the centre of the dry ingredients and stir just until combined.
Stir in the apple, raisins and cereal.
Place the batter in the muffin cups.
Sprinkle with extra cereal or cinnamon sugar if desired.
Bake in the centre of the preheated oven for 25 to 30 minutes or until a toothpick inserted in the centre of a muffin comes out clean.
Remove the muffins from the pan and cool on a wire rack.
Serve right away or place in a plastic bag and refrigerate for up to 3 days or freeze.
