Fat Brands Inc. /zigman2/quotes/201237501/composite FAT +13.25% stock soared 128% in Thursday trading after the company announced it was acquiring the Johnny Rockets chain restaurants from private-equity firm Sun Capital Partners Inc. for $25 million. The purchase, funded through cash on hand and proceeds from the company's securitization facility, is expected to be completed next month. Johnny Rockets is a 50's-style burger-and-shake chain with 325 locations around the world, including nine that are company-owned. The acquisition will bring Fat Brands' total number of owned and franchised locations to more than 700 with annual sales that exceed $700 million. Fat Brands stock has rallied 77% for the year to date while the S&P 500 index /zigman2/quotes/210599714/realtime SPX -1.12% is up 4.8% for the period.