I ate near-identical meals at In-N-Out and Shake Shack and found that while Shake Shack makes better fries, the other makes the perfect burger

As soon as I landed in Los Angeles, I headed for the nearest In-N-Out.

In-N-Out's vintage vibe and red-and-white tiling have made its aesthetic instantly recognizable.

It's got laid-back California charm for miles, and it's so bright and clean that the vintage decor feels cute, not old.

The decor isn't the only thing that is reminiscent of the past. In-N-Out's menu is the kind of simple, unfussy menu your grandma might have ordered from in her youth.

The chain famously sources most of its fresh ingredients from farms in California. Absolutely nothing is frozen and reheated.

My meal came out after a short wait: an animal-style Double-Double ($4.35), animal-style fries ($3.95), and a medium lemonade ($1.75).

I started with my animal-style fries because of the universal law of fries.

That is, that the quality of a fry is inversely correlated to the number of seconds it's spent in cold air, and the decline in taste is exponential.

Somehow, In-N-Out's fries defy the laws of physics. Even straight from the fryer, they taste like wet cardboard.

Take my advice: Skip the opening act and come for the headliner.

The Double-Double is large and petite at the same time. Even though it's a hefty burger, it's neatly contained in a cute wrapper.

Two fresh beef patties with melted American cheese, onions, lettuce, and tomato stacked into two toasted buns are smothered in special sauce and grilled onions.

It's as close to perfect as a fast-food burger gets. First off, everything tastes unbelievably fresh.

The beef is juicy and melds delightfully with the tangy cheese and sauce.

And the crispy, bountiful stacks of veggies add just the right amount of textural variety and freshness.

It's so juicy that a mixture of beef grease, tomato water, and special sauce leaked from the wrapper.

Some extra napkinry never hurt anyone, except maybe a few trees here and there.

However, cold fries caused many a metaphorical tear.

Naked or smothered in sauce, these potatoes managed to disgust no matter how I ate them.

After a few more futile forkfuls, I gave up. These were destined for the trash.

The burger, however, was destined for greater things.

Since each bite tasted so well-balanced, I never felt like I was stuffing my face — even though I was.

The Double-Double quickly became a nil-nil, and I left In-N-Out with a deep sense of digestive satisfaction.

Back in New York, some time later, the hankering for a hamburger hit again.

I went to the Shake Shack in Fulton Center. Like all Shake Shacks, it's minimal, industrial, and inaccessibly cool.

The menu is large and varied, even though Shake Shack started out as a simple hot dog stand. Chicken, beef, hot dogs, ice cream, mushrooms — Shake Shack has it all.

Danny Meyer, a chef with a fine dining background, founded Shake Shack as part of an effort to revive Madison Square Park.

Source: Shake Shack

Therefore, everything from the ingredients to the cooking techniques at Shake Shack carry that fine-dining finesse.

I got a ShackBurger ($5.99), fries ($3.09), and a cup of Shack-made lemonade ($3.09). It was pricier than In-N-Out. Would that price bump be worth it?

Again, I started with the fries. I should disclose that Shake Shack won my fry taste test back in June 2019.

Read more: I tasted french fries from 8 major fast-food chains, and the winner surprised me

There's a reason for that. Shake Shack's boldly crinkle-cut potatoes are impossibly crispy on the outside and melty-mashed on the inside.

The Shake Shack fry is the perfect fry, whether or not you agree with its choice of cut.

Unlike In-N-Out's sad slivers of soggy spud, these gave me what I wanted from a fried potato — and more.

They, too, defy the laws of physics by staying delicious long after they've left the fryer.

The ShackBurger is even teenier than the Double-Double. Shake Shack uses hormone-free beef.

I'm stunned that this small sandwich weighs in at 530 calories.

It's a simple cheeseburger topped with lettuce, tomato, and ShackSauce in a potato roll.

But the ShackBurger tastes far from simple. Its breakout star was clear from the first moment: the beef.

Everything in a ShackBurger is soft. There's nothing crunchy in here except the caramelized exterior of the patty.

The beef is unbelievably flavorful and tender, and it's clear the burger was constructed to let it shine — but, that means a less balanced burger overall.

The tomato was tart, the cheese pungent and tangy, and the ShackSauce ... saucy. But I found myself missing the zing of an onion and the crunch of a pickle or crisp, fresh lettuce.

It's still a really good burger, but it's unique. It doesn't quite have all the classic elements one desires from a burger.

Next, I opted for some lemonade.

Made in-house, the lemonade was a highlight.

Sweet, sour, and fragrant, it was levels above anything you can get from a soda fountain.

The burger, sadly, was gone before I knew it. And at the end of it all, I was still hungry.

Luckily, I had quite a few fries left.

When it comes down to it, Shake Shack's innovative flavors do make it stand out. But it still can't compete with a perfectly executed classic.

The Double-Double is a lip-smacking stack of beef, bun, and all their best companions. It's proof that there's truly no substitute for a classic that's just done right.