The answer might surprise you.

Until recently, I had no idea why a recipe might call for one or the other.

So I did a little sleuthing on oats and found answers that surprised me.

Quaker oats packaging

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Here’s what I learned.

What’s the Difference Between Old-Fashioned Oats and Rolled Oats?

That’s becauserolled oats and old-fashioned oats are the same thing, according to theQuaker Oats website.

oatmeal raisin clusters on a baking pan next to a bowl of oats

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So you should feel free to sub one for the other.

Rolled oats get their name from being flattened with rollers.

They cook quicklyin about 10 to 15 minutesand maintain some structure and bite.

Chocolate oat balls on a wooden board next to a scoopful of oats on the counter

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If you see a recipe that just calls for “oats,” chances are it means old-fashioned/rolled oats.

Instant Oats:Instant oats are frequently sold in individual-serving packets in plain and flavored varieties.

They are a throw in of rolled oats, but even thinner and more finely chopped.

However, if a recipe specifically calls for instant oats, go ahead and use them!

Steel-Cut Oats:On the opposite end of the spectrum from instant oats are steel-cut oats.

You may find them labeled as Irish oats or pinhead oats.

If you want something that cooks in one to three minutes, opt for instant or quick oats.

However, if you want a toothsome and tasty porridge and have time to spare, choose steel-cut oats.