Heat 1 1/2 cups water in a medium pot over high heat.
When it's almost about to boil, lower to medium low and add all ingredients except the milk and optional toppings. Cook, stirring often, until the oats are softened and the water is absorbed, about 8-10 minutes.
Put the lid on, remove from heat, and let sit for about 5 minutes. Stir in the milk and add optional toppings and serve warm.
Notes
If you have leftovers, try storing them in an airtight container overnight, then mixing them with plain whole milk yogurt the next day for a quick take on overnight oats.
If you need to cook gluten-free, simply choose gluten-free rolled oats.
To make this dairy-free, use your favorite dairy-free milk.
Grate the apple with the peel on to add nutrients.
Lower the heat and add a little additional liquid if the oatmeal sticks to the pan at any point.
Top with protein-rich nut or seed butter.
Stir in hemp seeds, flax seeds, or chia seeds to add fiber, protein and healthy fats.
To store, place into an airtight container in the fridge and then warm individual servings as needed for about 30 seconds in the microwave.
An older baby eating finger foods can eat this with their hands. A kiddo learning to use a spoon can be handed preloaded spoons so they can feed themselves with your help.