It’s All About the Crisp

Everybody loves good french fries – the crisp exterior with the fluffy interior, salty and delicious. A great companion to any meal or beer. On the other hand – deep frying in a small apartment can make your house smell like a fast-food diner’s kitchen for hours. So, for me, that triggered the search for the perfect oven-baked potatoes.

First let’s make one thing clear – I’m not in it for the “healthy option”, I want the deep-frying taste and I have no intention of skimming on the oil for “health”.

The first thing I tried is drying the potatoes with a paper towel before putting them in the oven – I didn’t see much effect. Then I tried salting them in different stages of the baking and I discovered that I prefer salting them in the last few minutes, the browning seems to be nicer but only slightly.

Next, I tried playing with oven temperature from 180° to 240°C (360° to 460°F). Higher temperatures did cause faster browning. I also tried flipping the slices at different times during the baking, and of course, you should flip them as we want the potatoes to evenly brown on both sides.

Another step I thought may be important was the rack I placed them in the oven – the closer to the top the more they will brown on the side facing up. On the other hand, the closer to the top the less even the potatoes cook as ovens don’t usually radiate heat evenly as it depends on the heat source physical structure (also I have quite a simple oven). You can see my oven’s radiating heat pattern in the image below.

Oil, I suspected, is very important as oil is very good at transferring heat – not enough oil and the potatoes will brown slowly – and you get something more similar to a cooked potato than a fried one. So, I sliced the potatoes evenly and mixed them in a bowl with oil, making sure each slice is fully coated with oil.

All this trying did give quite a tasty result, and my wife seemed content.

But I was not. The potatoes were tasty, but they did not have the crispiness I aspire to.

They may satisfy most, but not me. I will not rest until I get them crispy enough to forgo deep frying in my apartment, otherwise, I may need to move.

Finally, J. Kenji López-Alt came to my rescue, saving me from the need to find a bigger place to live, with his amazing book – The Food Lab. It appears that in order to get the potatoes to be crispy I need to par-cook them in water! who would have thought?

Apparently, cooking them a bit releases starch from them which later turns to crisp. Also, a large surface area gives more crispiness, so battering them up a bit without breaking them also helps by creating crevices in the exterior – it looks less pretty but I am willing to pay the price for extra crisp.

So, the rules to crispiness are – par-cook the potato slices in water, drain, coat with oil, and put in the oven. All other details are not critical.

You may wonder, which oil should I use?

Avoid low smoking point oils, like olive oil or whole butter, burned oil can ruin the taste. You may want to try animal fat, as many people swear by the taste of potatoes fried in animal fat oil. I usually use canola oil as it is easy to come by where I live and I like its neutral taste.

One last tip – salt the water when you cook the potatoes, like in mashed potatoes, it gives a better homogenous saltiness than salting the finished dish.

After the success with potatoes, I had to try the same method with sweet potatoes. And though it didn’t come out as crunchy as the potatoes it was still great – better than just sticking them in the oven. One thing to note, sweet potatoes get even softer than potatoes when cooking them – so you need to take them out from the water after less than 10 minutes – try gently testing them with a fork to see if they are soft enough.