Since leftover steel-cut oats only improve with a few days storage, I always make a large batch. Leftover oatmeal can be refrigerated for up to a week. Some folks like to portion it out into glass jars for ready-to-grab breakfasts.
A note on the recipe source: These muffins with dried cherries are adapted from Tyler Florence’s Real Kitchen by (of course) Tyler Florence. He includes poppy seeds, which I omitted because they get stuck between my teeth.