Steel-cut oats completely miss the point of oatmeal. For one thing, they take forever to cook. I would be willing to overlook this if the final result were stick-to-your-ribs spectacular. It is not. The final result is usually a bunch of chewy little grain nubbins suspended in a hot, viscous liquid. It is not soft, it is not creamy, and it is not comforting.
To find those qualities, you need rolled oats. These are slightly less nutritious, but far more pleasant to eat for breakfast. Steel-cut oats are hulled oats (a.k.a. oat groats) that have been very minimally processed (i.e., cut into pieces). Like brown rice and other whole grains, they are lovely in pilafs and salads. Rolled oats are groats that have been flattened, steamed and toasted, a process that makes them more shelf-stable and much quicker to cook. (Rolled oats take 5 to 10 minutes, steel-cut oats more like 30.) Unfortunately, many oat processors take this a step or two too far: Quick and instant oats are rolled oats that have been pulverized to the point that mushiness is inevitable. But the sweet spot — those rolled oats labeled old-fashioned or thick rolled — is truly sweet: These oats end up tender and thick, and there's just enough sturdiness in each one to prevent the porridge from dissolving into sludge.
It needs some help, though. Oatmeal should always be cooked in approximately equal parts water and milk. If you make it with only water, it won't be nearly creamy enough, and you'll be hungry again an hour and a half later. If you make it with only milk, you'll have to watch it like a hawk to prevent the dairy from sticking, burning and/or forming an icky skin. Lactose intolerance and veganism are no excuses for using only water: Non-dairy milks, especially almond milk, are great in oatmeal.
Then there are toppings. There is nothing wrong, exactly, with a pat of butter and a trickle of maple syrup, but, despite the richness of each of these toppings, this combination feels anticlimactic. Fresh fruit seems nice in theory, but raw fruit on top of cooked oatmeal is the culinary equivalent of fingernails on a blackboard; I would not wish the disconcerting mouthfeel of cold, crunchy strawberries on top of warm, smooth oatmeal on my worst enemy. The solution is to cook the fruit and bring it to roughly the same temperature and texture as the porridge. Among their myriad other useful properties, apples are perfect for sauteing and serving on oatmeal. Use cooking apples if you want firm, distinct slices, eating apples if you don't mind them disintegrated.