Peel and chop the apple into large chunks. Steam the apple chunks until soft. You can also boil it.
While the apple is cooking, place the oat milk in a pot and bring to a boil. Add the oats and reduce the heat to low. Stir frequently until the oats are soft and have absorbed most of the liquid. About 5 minutes. If you feel the oatmeal looks dry at this point, feel free to add a splash of milk and stir. Add the cinnamon and stir until well combined.
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