Both of the France international's goals were sandwiched between strikes from Ronaldo, who took his tally to 13 for the season and earned his 22nd hat-trick in the Spanish top flight.
Benzema came under fire from sections of the home support earlier in the campaign after Madrid's sluggish start to the season, which included defeats to Real Sociedad and city rivals Atletico.
However, the 26-year-old's name was sung around the Santiago Bernabeu after taking his haul to five in all competitions, and Ronaldo was impressed by another strong display.
"I'm happy for him [Benzema]," he is quoted as saying by AS. "He is the best striker in the league and one of the world's best.
"Criticisms are part of being a professional footballer and we have to be above such things.
"We [Benzema, Gareth Bale and Ronaldo] like it [their partnership], we're used to playing together and are very happy."
Sunday's win took Madrid's tally to 20 goals in their last four league matches but, worryingly for their rivals, Ronaldo believes there is still room for improvement.
"We are improving," he added. "As the coach said at the press conference we are improving in some aspects and we are growing, we have room for improvement.
"The team has played well and the team has scored five goals without reply, we are very happy."
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