The Portuguese netted his 23rd career hat-trick for Madrid with a treble in Saturday's 5-1 win over Real Sociedad.
"Cristiano is special and spectacular - he gives his best in every match," Varane told the club's official website.
"The first half was very good in attack and defence. We are very proud of how we played.
"We always try to play like we did in the first half. We're are improving the way that we are playing and we have to keep working hard to improve every day."
Ronaldo has now scored 225 goals in 216 games for Madrid.