The currently browser-based system was trialled within Lugger's own Paris-founded restaurant group - which operates Gloria and Circolo Popolare in London - and will be used by over 1,000 restaurants across the UK, France, Spain and the US when it soft launches this summer ahead of an official launch towards the end of the year.
UK venues using Sunday will include Corbin & King and Gymkhana and Hoppers-owner JKS Restaurants. Investors include New Wave, a venture capital firm backed by French telecoms billionaire Xavier Niel, and Coatue Management.
Sunday will soon open offices in London, Paris, Madrid and Atlanta with Lugger leading the business outside the US as CEO (there will be a seperate CEO in the US).
Tigrane Seydoux, with whom Lugger founded Big Mamma in 2013, is non-executive chairman.
The QR-codes that link the customer to their tab are placed on the table at the beginning of the customer's experience, meaning they are able to settle the bill without having to attract their server's attention.
Lugger says that Sunday's key USPs are the ability to pay in as little as seven seconds (assuming phones have Apple Pay, Google Wallet or similar) and will be "two to three times cheaper" in commission charges than comparable alternatives.
"This is the fastest way to pay in restaurants in the world, and it's also the simplest and cheapest. We're being robbed by banks," he says.
"Most restaurants eventually end up paying more than 1% through fixed costs, such as renting card machines, and variable costs. Payments in bricks and mortar is something that has not been challenged for 40 years."
Lugger says that the low commission fees will be achieved by a high volume of payments, and that the introduction of open banking technology further down the line could lower payments even further.
"We launched at Big Mamma last July. 80% of our customer paid vid Sunday. Since we've reopened for outdoor trading this week it's 90%. That's extraordinary."
Lugger says the average spend increased by 10% for customer using Sunday and the new technology saved each table an average of 15 minutes, allowing Big Mamma to turn tables faster.
"We raised a large amount because this isn't about building a B2B platform. We want to change usage. We live in a world where people shop with Ocado and order cabs on Uber, yet it still takes up to 15 minutes to pay at a restaurant using a credit card machine."
"This is old technology. You don't need to bring the bill to make sure you clients had a good time. You can use that saved time to improve the experience for the customer," adds Luger.
Sunday will launch its own app before the year is out and will also eventually move away from QR codes in favour of a more modern solution such as near-field communications, a contactless technology that links two devices.