Ingredients (5)

1 cup (6 1/3 ounces; 180g) steel-cut oats (also sold as pinhead or Irish oats; see note), such as Bob's Red Mill

3 cups (700ml) cold water or whole milk (or some combination thereof), plus more water if needed (see note)

Kosher or sea salt

Unsalted butter or cream, for serving (optional)

Brown sugar, for serving