(TrendHunter.com) The Johnny Rockets Birthday Cake Shake is being launched by the diner restaurant chain to provide patrons with a tasty way to celebrate the brand's 35th birthday. The shake starts off with the... (TrendHunter.com) The Johnny Rockets Birthday Cake Shake is being launched by the diner restaurant chain to provide patrons with a tasty way to celebrate the brand's 35th birthday. The shake starts off with the...