I went to Shake Shack for the first time. My nearly $60 meal for 2 tasted good, but the portion sizes felt a little stingy

• I ate at Shake Shack for the first time. My friend and I spent $57 on burgers, fries, drinks, and frozen custard.
• My vegan burger tasted delicious and I'd definitely order the frozen custard again.
• But I was disappointed by the cheesy fries and my friend had expected a bigger burger.

I'd heard good things about Shake Shack, the burger and frozen custard chain that started life as a hot dog stand in New York City.

My friend gushed about its cheesy fries after returning from New York, and I'd seen billboards advertising its delicious-looking vegan crispy shallot burger.

So I decided to give it a try.

Shake Shack first came to the UK in 2013. It now has 15 restaurants in the UK and three delivery kitchens.

I went to the Shake Shack in Stratford, located in a shopping mall near London's Olympic Park, to see what the hype was about.

Upon entering the restaurant, I was struck by how upmarket it looked for a fast-casual chain. The interior mainly consisted of subtle, natural colors — there was lots of exposed wood, green and black paint, and what I took to be fake plants.

You could place orders with a staff member at the counter, next to the pickup spot.

But while I was there, I only saw customers placing orders at the three digital order screens. Digital kiosks are a massive priority at Shake Shack.

Source: Business Insider

The chain’s execs have said that they’re Shake Shack’s biggest and most profitable order channel and that customers place orders that are, on average, more than 15% bigger than orders placed at a cashier.

Sources: Business Insider, Shake Shack earnings call

There was also a stack of printed menus, which I found unusual. This may have been for people who ordered with a member of staff or who wanted to browse the menu at their tables before ordering at a kiosk. It gave a better overview of the full menu than the kiosk screen did.

The kiosk was easy enough to operate.

I was able to customize some of the items, like adding pickles and tomato to my Crispy Shallot Burger for no extra cost. I wouldn't have thought to have asked for these at a staffed kiosk.

I felt like Shake Shack had a slower ordering process than other fast-food chains, though. I was surprised that it asked for my collection date and time when I was placing an in-store order.

When your order was ready, staff called your name, which was also displayed on screens in the seating area. The screens meant you could sit down to wait for your food to be prepared rather than having to stand by the pickup counter.

While I waited for my food, I looked at the decor. The kitchen was open plan, which is increasingly common at quick-service chains, and there was a foosball set.

I noticed that some of the tables were labeled as being made in Brooklyn from former bowling lanes. I felt that there was a contradiction between the eco-friendly upcycling and the final product then being shipped across the Atlantic.

In the UK, Shake Shack sells a range of beef, chicken, and vegetarian burgers, frozen custard, and milkshakes. You can also get hot dogs and crinkle-cut fries, as well as soft and alcoholic drinks.

Digital screens, including the order kiosks, advertised some of Shake Shack's limited-edition items. These included a couple of Al Pastor burgers — a flavor that burrito chain Chipotle has seen huge success with.

Source: Business Insider

My friend and I ordered a Crispy Shallot Burger, a ShackMeister with bacon, a pot of Shack Sauce, a portion of cheesy fries, and two large drinks. The drinks were massive.

My friend had the ShackMeister. The base price was £9.25 ($11.50) for a single patty, though he paid an extra $1 to add bacon. My friend thought the burger was delicious but was disappointed by the size — he said it definitely wasn't filling enough. Perhaps he should have got a double.

My friend said that the bacon was fairly priced and an "excellent addition." He chose the burger partly because of the crispy shallots it included, which we both thought were an interesting addition and differentiated Shake Shack's burgers from those sold by other chains.

My vegan Crispy Shallot Burger cost £9.55 (about $11.90). It contained a vegan fake-meat patty topped with vegan cheese, beer-marinated crispy shallots, lettuce, and Dijonnaise sauce. I added pickles and tomatoes to my burger for free.

The patty, which Shake Shack said is bespoke for the chain, tasted delicious. I was glad I added the pickle and tomato which gave the burger an extra crunch. I usually avoid mustard, but the Dijonnaise sauce gave it a tasty tang. It was a delicious burger.

But I was disappointed in the portion of the cheesy crinkle-cut fries we got to share. I felt like the fries were underseasoned — they tasted bland — and the cheese sauce was very thick and tasted artificial. There wasn't enough to spread over all the fries, too.

For £5.25 ($6.50), the portion seemed quite small, and unlike many other chains that offer a range of sizes for their portions of fries, there was only one size available.

For £1 I added on a tub of ShackSauce. It tasted great and gave my fries some much-needed flavor. To me, it tasted just like garlic mayo. Serious Eats suggests you can make a copycat sauce from mayo, ketchup, mustard, chopped dill pickle, garlic powder, paprika, and cayenne pepper.

Source: Serious Eats

Of course, we couldn't go to Shake Shack without trying its famous frozen custard. You can get chocolate or vanilla frozen custard in a cup or cone, or you can choose from a range of so-called "Concretes" that come with toppings. We ordered the Sticky Toffee one to share.

This was delicious. I love creamy desserts, and the frozen custard was basically thick ice cream. The toppings were tasty and didn't cost much more: Our £5.60 ($7.10) Concrete only cost £1.35 more than a plain one-scoop portion of frozen custard.

We got a milkshake to share, too. The portion seemed quite large, though I was surprised that the shakes only came in one size. After having the delicious, rich, thick Concrete, our £5.90 ($7.35) Cookies and Cream Shake seemed a bit underwhelming.

In total, we spent £45.85 (just over $57) at Shake Shack, which seemed like a lot for a meal for two at a fast-casual chain. But we did get a lot of food because we wanted to try out the menu: two burgers, two soft drinks, fries, a shake, a Concrete, and a tub of sauce.

I enjoyed the vegan burger and loved the Concrete, but if I came back I'd skip the fries and shake. Though our large soft drinks were massive, my friend said the burger sizes were more like snacks than full meals. After his burger and half the portion of fries, he was still hungry.