“Simply Crispy,” a pop-up shop selling exclusively “crisp sandwiches,” sold out just two hours after setting up shop in Belfast on Monday.

The crisp sandwich is a true Irish classic – all you need is two slices of bread, butter, and a bag of your favorite crisps (potato chips).

Simply Crispy owner Andrew McMenamin said there’s been an overwhelming demand for cheese and onion baps – that is, Tayto’s cheese and onion flavored crisps crushed between a floury Belfast bap, a classic weighty white bread that’s tougher on top but fluffy on the inside.

A parody on satirical news website The Ulster Fry inspired McMenamin to temporarily transform his business, “That Wee Café” on Belfast’s Bedford Street, into the crisp sandwich shop and it’s been a massive hit. Lines were snaking out the door all throughout lunchtime.

The article, entitled “Crisp sandwich gets new lease of life in hip Belfast eatery” spoofed London’s new “Cereal Killer Café,” a cafe opened by Belfast twins specializing in breakfast cereals.

“We read that article about the crisp sandwich in the Cathedral Quarter and it struck a chord, it was so funny,” he said in an interview.

“I think we needed it to be as close to the original article as possible.” The plan is to keep the sandwich shop open for three to four weeks but he is willing to play it by ear, said The Belfast Telegraph.

The shop boasts 35 types of crisps to choose from, mostly from Tayto, which is on board with the operation. Aside from classic crisps they also offer novelty options like Frazzles and Monster Munch, inspired by a sign in the satire’s image that says “Daily Special: Monster Munch on Ormo.”

“I have been told it is the world's first [crisp sandwich shop]. It’s a school thing; people remember it from their school days, and it is a classic and it is old-school,” he said. “We are riding on the back of the publicity the cereal cafe got in London – if it helps us and Ulster Fry then it's a good thing.”

McMenamin said that all of their products are local and “true to Northern Irish product.” Tayto, based in Northern Ireland, is one of the largest distributors in the UK.

The sandwiches come with tomato soup and chips (French fries) and the meal costs around $4.50. Customers can add meat or cheese to the sandwich, and a sign in the store says they’ll even cut off your crusts free of charge, mimicking a sign in the satire’s image that says: “No crusts? No problem! Add 50p.”

While many people waiting in line on the first day were in their 20s, there were quite a few businessmen and women lined up as well. The Belfast Telegraph said the atmosphere inside the shop was jovial, and many people were taking “selfies” to post on social media.

32-year-old Nerys Coleman, who works for a foreign direct investment data firm, said the nostalgia factor of “Simply Crispy” attracted her most.

“It is something from your childhood. I have not had a crisp sandwich since university and before that childhood so it is bringing back the nostalgia,” she said.

Another customer said: “It’s a good idea because it's something most people have tried. I would have a crisp sandwich during work no problem.”

The shop idea has been credited to Ulster Fry comedy writers Seamus O'Shea and Billy McWilliams.

How to make your own crisp sandwich:

1. Lightly butter two slices of bread, then open the packet of crisps and carefully lay them out on the first slice of bread.

2. Carefully break and flatten the crisps with the flat of your hand as you add them on to allow for a more even spread.

3. When the entire packet has been added to the bread, carefully lay the second slice of bread on top and cut in half.

(*Add other sandwich ingredients if you like, i.e. cheese slices.)

“Simply Crispy” offers a side of nostalgia with their classic crisp sambos.YouTube