The 30-year-old has been a vital source of goals since Leicester returned to the top flight in 2014 and he reached a personal milestone with another strike against United.
A long ball forward caught out the United defence and, after Riyad Mahrez had been held up on the edge of the box by Chris Smalling, the Algerian rolled the ball into the path of Vardy to finish clinically past David de Gea on 27 minutes.
There was a coincidental note to Vardy’s 50th Premier League goal as his first also came against United when he scored in Leicester’s memorable 5-3 home win over the Red Devils in September 2014.
42% - 21 of Jamie Vardy's 50 Premier League goals (42%) have come against 'big six' opposition. Banged. — OptaJoe (@OptaJoe) 23 December 2017
The England international also scored against United at home in the 2015/16 season en route to Leicester’s stunning Premier League title success under then-manager Claudio Ranieri.