The Great Baked Fry Experiment

The Great Baked Fry Experiment

In which I try to perfect the baked french fry. Sweet potatoes are hard to get right.


The Great Baked Fry Experiment

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There are a few things you should know before you get too far into this post. First, I’m pretty bad at the scientific method. In fact, I don’t exactly even know what it is. I’m not a scientist and have never claimed to be one. So when I try to “test” something, I’m sure my methods are far from perfect.

Second, and possibly more important for this post, I believe that the best fry is a fried fry. Baked potatoes are good and baked potato skins and wedges are indeed tasty, but for french fries… give me a vat of hot oil please.

I put both of these truths aside though when I got this message from a good friend:

I ask that Macheesmo figure out how to make CRISPY fries and sweet potato fries in the OVEN.

And so over the next three weeks, I embarked on a scientific (sort of) endeavor to determine how to make good baked fries.

This turned out to be incredibly hard. I did my best to standardize the things that I could standardize. First, I tried to cut all my potatoes into 1/2 inch sticks. Second, I baked every batch regardless of normal potato or sweet potato at 400. That said, I’m fairly certain that my oven is probably off by 10-15 degrees in either direction and I’ve never taken the time to calibrate it. Remember what I said about me sucking at the scientific method?

Baking time for each batch was around 30-35 minutes for normal fries and 20-25 minutes for sweet potatoes, turning a few times throughout.

Just as a control (is that the right word?), I baked a small batch of potatoes with absolutely nothing on them. Cut them up and threw them in the oven.

This was the result:

naked potatoes


They were crispy! Unfortunately, they tasted like old shoes. Nobody in their right mind would call this a fry.

The Variations

Before I go through all the various kinds of fries I made over the last three weeks, I wanted to quickly lay out the different variations I found in my research that can either be applied before and/or after the baking process to result in deliciousness. (Am I sounding science-y?)

Naked – Nothing on them and nothing done to them. Potatoes au natural. Also known as gross.

Blanched – After slicing the fries, cook them for a minute or two in boiling salted water to remove some starch from them. This double cooking should make them crispier when baked. Be sure to pat them dry before baking.

Ice Bath – Similar to the blanching idea. By letting them sit in ice water for 30 minutes, they will supposedly be crispier when baked.

Olive oil – My oil of choice. Every fry variation gets 1 Tablespoon of olive oil per 1/2 of a potato. It’s possible that this was too much olive oil, but it’s what I started with so I just kept it up throughout.

Kosher Salt – Most essential. This doesn’t really help with crispiness as far as I could tell, but who wants a fry without salt?

Cornstarch Mix – A light mixture of cornstarch and various spices. Applied to the potato after blanching, it gives the potato a crusty exoskeleton of sorts.

Brown Sugar Mix – Only good with the sweet potato variety, but same idea as the cornstarch mixture.

Normal Potatoes

The Russet potato was my first subject. I tried basically ever reasonable combination of the above things and most actually worked pretty well.

Even if you do potatoes naked with some olive oil and kosher salt, I was able to get a pretty crispy result.

baked with oil

But the real trick, I think, is in the blanching. Just a few minutes dipped in boiling salted water. Then let them dry on a paper towel.

Blanching the things
A quick dip

As I mentioned above, I mixed up a corn starch mixture to apply to one version of these fries. This was the basic ratio:

Corn Starch Mix

– 1 Tablespoon corn starch
– 1/2 Teaspoon kosher salt
– 1/2 Teaspoon garlic salt
– 1/2 Teaspoon hot paprika

The seasonings are completely adjustable depending on your tastes. Go crazy! I tried to keep mine the same throughout… you know… for SCIENCE.


Fries, when blanched and then lightly dusted with a teaspoon or so of this mixture do get a crunch exterior that’s very tasty!

with starch
Lotsa flavor.

Normal Potato Results

I got the best results from the blanched potatoes. I think they were as crispy as baked fries can be. Personally, I’m a minimalist when it comes to fries so I preferred the ones with just olive oil and salt, but I can see how the corn starch variety would be very well received.

My Sweet Potato Nemesis

Normal Russet potatoes worked out okay, but I knew that the real battle was going to be with these suckers:

Sweet Potato spears
Tricky business

Before I get too far into it, I know that there are a few different varieties of sweet potato. There’s a variety that is white on the inside like a normal potato, but is just, well, sweeter. I tried a few batches of that variety and found that they cooked very similar to normal Russet potatoes.

I knew my friend was referring to the yam potato though – the orange kind – when he said sweet potato, so that’s what I focused on.

These were a completely different beast than the normal fries. Just to give you an idea naked sweet potatoes baked in any fashion, I found, produced completely soggy results. Limp. Soggy. Fries. Actually, they tasted okay because sweet potatoes are good, but not what I was going for here.

The Ice Bath

I found that soaking the sweet potatoes in ice water had an effect. It definitely changed them somehow to produce a slightly crispier fry. The key is to make sure you let them soak for at least 30 minutes and dry them well before baking.

Ice soak
New methodologies…

Sweet potatoes were very hard to get crispy at all. Things that did not work:

1) Naked. No matter what I tried, baking sweet potatoes naked just ends in sogginess. They work well in casseroles or baked whole, but they don’t work for fries like this.

2) Blanching. Shockingly, it was tough to get them to crisp up after a blanch. I actually thought this would work well, but it completely flopped. The one exception to this was with the cornstarch topping. They were somewhat crispy like that, but not great. I actually think that the fries somehow absorbed water in this process which made them less likely to become crispy.

Again, The Ice Bath

I must say that for sweet potatoes, the ice bath worked. It’s important to make sure you pat them really dry after a 30 minute soak, but even with just some olive oil and salt they crisped up decently.

not bad
Doing okay!

I’ll be honest though (my job as a scientist here). The kind of crisp achieved with the ice bath and the oil and salt is not ideal. It’s very tasty, but not ideal.

That said, I had much better results with the sweet potatoes, ice bath, and cornstarch.

I also tried a brown sugar mixture: 2 Tablespoons brown sugar, 1/2 Teaspoon kosher salt, 1/2 Teaspoon pepper, 1/4 Teaspoon cayenne. If you toss the fries in some oil and then this mixture after they are dried from the ice bath, the sugar produced an almost caramel crust around the fries. They’re crispy and flavorful. The only downside is that it’s almost unavoidable that due to uneven oven heat, some of the fries will get some burned sugar on them.

If you do the brown sugar topping, it helps to bake them on parchment paper.

The flavor was generally good though.

brown suga
Crispy… or crunchy?

To be completely honest, I don’t know how scientists do it. After weeks baking fries, at the end of it, not only were my methods slipping, but I completely lost track of what result I was looking for. I forgot what a crispy fry even looked like!


If you must bake:

Normal Potatoes: Blanch and the either go with the olive oil, kosher salt traditional topping or try a cornstarch mixture.

Sweet Potatoes: Ice bath is key for 30 minutes (and yes I tried one for 10 minutes and it failed). Then go for either the olive oil and kosher salt, cornstarch topping, or brown sugar mixture. You’ll get the best crisp from the cornstarch or brown sugar mixtures.

After all that though, I have to say I’m defaulting to my standard. Give me a pot of hot oil and I can make crispy sweet potatoes or normal potatoes and season them perfectly after they get out of the oil.

And so ends The Great Baked Fry Experiment… Unless people have comments on what I did wrong, which I’m sure people do! So where did I go wrong? What did I miss?

The Great Baked Fry Experiment

13 Responses to “The Great Baked Fry Experiment” Leave a comment

  1. Well, all in all, you look like you went all scientific. I just remembered something that I heard a while back – try soaking your fries in vinegared water. It is supposed to help maintain the crispiness. Not sure why. LOL

  2. There is a trick my mother taught me that seems to work to crisp up even oven baked "fries?" and give them a nice salt flavor. Take a paper grocery bag (I know not the most sanitary, however in 50+ years I'm living proof there's only a small chance of getting sick) dump your fresh out of the oven potatoes inside — sprinkle with salt and other spices — I like pepper too vinegar for some — give them a good shake. This tends to crisp things up while also eliminating any excess oil. I have always found it diff to really season the potatoes during cooking — McDonalds does the same thing — by sprinkling with salt after cooking.

  3. Wow, Nick; I think you're to be congratulated for going through all this. When did you have time for your day job?

    As for me, the best oven-baked fries I've ever made — and I say this as somebody who can make Julia Child's Bouche de Noel with meringue mushrooms — is from a bag of frozen Fast Food Fries from Ore-Ida. But I'll deny I ever said it.

  4. ohhh and dipping the sweet potatoes in an egg white bath, then dipping them in seasoning and putting into a very hot oven should yield crispy-ness!

    or you could burn a slipper and dance backwards — ha!

  5. AWESOME! Thanks for the detailed baked fry info! We've been struggling to perfect oven fries for awhile, sometimes with good results and sometimes with soggy results. Never thought of blanching then baking. Genius!

  6. I respect all these different things you did and I'm going to try the ice water thing for the sweet potatoes. I can usually get a good crispy oven baked fry because I use a baking stone. I get it really hot first, rub with a little olive oil. A little oil goes a long way with baking stones. Mine is very seasoned. Also, I use cast iron fry pans (almost every day) and most often for oven use. The baking stone is a rectangular (about the size and style of a jelly roll pan). We use it every day; works well for roasting vegetables (and getting that caramelization) and for home fries.

  7. I make oven fries all the time… I actually made some last night.

    Though I had never blanched russets or put sweet potatoes in an ice bath until after I read your blog. I’m not sure the blanching made much of a difference for me. But the ice bath was definitely a good tip. (Thanks!)

    I usually bake my fries a lot hotter (per the instructions of the great Martha Stewart) – at 450 degrees – but for the same amount of time. 30 min. for russets. 25 for sweet potatoes. I think that helps the crispy effect.

    Also… I usually use a flat 14 x 17 cookie sheet (the kind with no sides). I think it helps the heat and air circulate over the fries better. You might want to try it.

  8. It sounds as though you used the same methods as I do for sweet potato fries.

    Yet mine always turn out crispy and firm…. sometimes with floppy centers on long fries.

    400 degrees, preheated

    sliced about 1/2" thin

    tossed with olive oil and paprika,

    baked for 10 min flipped and then another 10 min.

    When I cut them in rounds like chips and thin they come out really crispy and delicious.

    (I don't know what it is about paprika on sweet potatoes but they just go hand in hand)

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