Wash the banana, peel it, and slice it.

Bring the milk to a boil in a saucepan. Then add the oats. Cook on medium heat for about 5-10 minutes depending on the consistency of oatmeal you want to achieve. Add some water during cooking if necessary. Stir occasionally. Towards the end of cooking, add the sweetener and mix well.

Transfer the cooked oatmeal into a bowl. Arrange banana slices on top.