The Ballon d'Or holder registered an eight-minute hat-trick before half-time - the quickest treble of his Real career - and then added two more after the break at the Santiago Bernabeu.
Ronaldo's fifth goal - an injury-time header - took him to 300 goals for the club, making him the third player to achieve that feat after Real legends Raul and Alfredo Di Stefano.
Former Spain skipper Raul scored 323 goals in 741 games for Real, while Di Stefano's tally stands at 308 from 396 outings.
Ronaldo reached the 300 mark in an astounding 287 games, with 214 of those goals coming in La Liga. The Portugal captain has 60 to his name in the UEFA Champions League, as well as 21 in the Copa del Rey, three in the Supercopa de Espana and two in the European Super Cup.
After his stunning display on Sunday, Ronaldo tweeted: "Happy to have scored 5 goals with this excellent team work. Thank you for all your support."
Ronaldo now sits eighth in La Liga's all-time scoring charts, having overtaken Pahino, who scored 211 times in 278 games for Real, Celta Vigo and Deportivo La Coruna in the 1940s and 50s.
