Came up with this method after trying:
Stovetop (hit or miss)
Oven (volcanic eruption)
Microwave oven (ditto)
Bowl in pressure cooker (too much cleanup after)
Directly in a slow cooker (hard "booger" crust on top)
For 2 perfect servings, you'll need:
A large programmable slow cooker
A heat-resistant bowl big enough for the water and oats that fits entirely inside without touching the sides or lid
2 cups of water
Traditional steel-cut oats (not quick cooking) and water for 2 servings as directed on the canister
Pour 2 cups of water into the bottom of the slow cooker. Lower in the bowl and measure in the oats. You can cover the cooker and wait until just before bedtime before continuing.
Add the water as directed to the bowl, saturating the oats without stirring. Poke any floaters below the surface.
Cover and cook 8 hours on Low. Time it so the oats don't sit in keep-warm for longer than an hour.
Come the dawn, carefully remove the bowl and set it on a folded dishtowel. Stir the oats, scraping as much of the "oat line" into the rest. Divvy up, flavor as desired and enjoy.
After the bowl cools, fill it to just above the residual oat line with cold water and soak until it's time to do the dishes. What's left will slide right out before you throw it (well, carefully place it) in the dishwasher. Dump the water from the crock and give it a quick going over with a damp dish cloth.