Samu Manoa scored a hat-trick for the hosts at Franklin's Gardens as Northampton recorded their fourth consecutive win in the league.
"The scoreline was comfortable but I think Sale had a fair share of possession. We were ruthless in attack," Mallinder told BBC Sport. "There are times when you go to your strengths of the maul and the scrum but we combined that with playing as well.
"The attitude of the players to put their bodies on the line and keep their shape and focus was outstanding."
Northampton start their European Champions Cup campaign next Saturday when they travel to France to face Racing Metro.