For Rolled Oats:
Combine oats, milk, and water in a pot.
Bring to a boil, then reduce heat.
Simmer for 5-7 minutes, stirring occasionally.
Remove from heat and let sit for a few minutes.
For Instant Oats:
Combine oats and milk in a bowl.
Microwave for 1-2 minutes, stirring halfway through.
Let sit for a minute.
For Steel-Cut Oats:
Combine oats, milk, and water in a pot.
Bring to a boil.
Reduce heat and simmer for 20-30 minutes, stirring occasionally.
Remove from heat and let sit for a few minutes.