Benzema scored a brilliant brace to inspire a 3-0 LaLiga win over 10-man Valencia at Madrid Castilla's Alfredo Di Stefano stadium on Friday (AEST).
After opening the scoring just past the hour-mark, Benzema completed the victory in stunning fashion with four minutes remaining – rifling a volley past Valencia goalkeeper Jasper Cillessen following Marco Asensio's 74th-mintue effort.
Benzema's two-goal display in the Spanish capital took his tally to 243 goals for Madrid across all competitions, leapfrogging club great Puskas (242) for fifth on the all-time list.
"It was a great goal, for the move and the finish – I'm delighted for Karim's goals," Zidane said after Madrid moved back within two points of leaders and rivals Barcelona.
It was a memorable outing for Asensio, who marked his long-awaited return by scoring with his first touch against Valencia.
Asensio sustained an anterior cruciate ligament (ACL) injury last July and returned to the pitch as a 74th-minute substitute on Thursday – the Spaniard's impact immediate.
"This means a lot for him. We're happy to see him back on the pitch," Zidane said. "After so many months out, to come back and score a great goal in his first involvement makes me really happy.
"He was already happy just to get out on to the pitch and then he was able to score straight away, which shows he is already involved."
Eden Hazard also impressed for Madrid – the Belgium star combining with Luka Modric to tee up Benzema for the opening goal in Madrid.
Injury and fitness have hampered Hazard's maiden Madrid campaign, but the former Chelsea attacker showed glimpses of why Los Blancos invested so heavily in the 29-year-old.
"This was a really good game from Hazard," Zidane added. "Physically, he was good and played 80 minutes. Sometimes you might think he's starting to look tired, but then he picks up the ball and sprints away."
Madrid remain within touching distance of Barca with nine matches remaining in the coronavirus-impacted 2019-20 LaLiga season.
On the title race, Zidane said: "We know that it will be like this until the end, but today we can be happy because of what we've done in the game.
"They are the ones fighting; we have to enjoy and congratulate the players because it was a complete game and then think about the next game against Real Sociedad."
Barca will face third-placed Sevilla on Friday and Zidane said: "We depend on what we are going to do, knowing the situation. I'll watch the game, but I don't have the idea in my head that Barcelona will slip up; we have to think about ourselves."