Steak ‘n Shake is updating its menu, remodeling the restaurants’interiors and adding ordering kiosks to switch the 88-year-old restaurant brand from full-service to quickserve. The company will spend about $50 million on what Sardar Biglari, chairman of the board of parent company Biglari Holdings, called a “radical transformation” that will update the brand’s business model for the 21st century. QSR