Bring the milk to the boil in a small saucepan, stir in the oatmeal with the whisk and let it soak for a few minutes over a low heat.
Wash and peel the apple and rub it all over with a glass grater until the core remains. Mix the grated apple with the oatmeal porridge and season with a little cinnamon.
The porridge is ready in no time and is a healthy evening meal for the baby.