The news comes as the company reveals details of a new site in London and of its first restaurants outside of London, reaffirming its plans to grow following the receipt of £3.5m of investment from private equity firm Quilvest at the end of last year.
Founder Brandon Stephens said the new investment was purely for expansion: "The financing from Santander provides us with the capital necessary to execute our objectives for growth and will allow us to pursue a number of exciting expansion initiatives within the M25 as well as outside of London."
Tortilla's latest site - at The Strand in London - opens today and will join its eight other locations around the capital. Stephens said the group was also in discussions for a further site in central London which could open in January 2013 and another in northern England.
The restaurant chain's first site outside the capital will open at the redeveloped Wintergarden at Kent shopping centre Bluewater on 9 October where it will join operators such as Leon, Nando's and Hamburger Heaven.
Its second site outside London will be within the Food Court at Hammerson’s WestQuay shopping centre in Southampton, which re-opens in November following a £5m upgrade.
Sarah Fox, head of catering for Hammerson, said: “We are delighted to welcome Tortilla to our newly reconfigured Food Court at WestQuay. Tortilla have proven themselves to be an excellent operator in the fast casual dining sector delivering a consistent quality product and is one of the exciting successful younger brands about to expand outside London."
The company, founded by Californian entrepreneur Stephens in 2007, counts YO! Sushi chief executive Robin Rowland as a non-executive director and Rob Lucy as head of property acquisitions. Lucy is currently on the look-out for more sites to expand the brand to, according to Stephens.
Stuart Donald, director at Santander Corporate Banking, said the brand was an 'ideal fit' with its own business's aim to support small and medium sized businesses.
"The strong management team and proven business model makes Tortilla an ideal fit with Santander’s commitment to support strong and viable UK companies as part of our wider aim to become the SME bank of choice," he said.
As well as expansion, Stephens said the restaurant group was continuing to evolve its menu honing its current ingredients and introducing a barbecoa shredded beef tortilla to its new sites.