The Reds were going for the title when Mourinho brought his Chelsea side to Anfield towards the end of the 2013-14 season, stopping the Merseysiders in their tracks as the Blues recorded a 2-0 win.
Liverpool never recovered from that setback on a frustrating day for Henderson and the rest of the team, a result the skipper says still haunts the club.
Henderson, who was suspended for that game with Chelsea, feels a win on Monday night against Mourinho's new side United will go a long to banishing memories of that infamous loss and he claims the team will be ready for any trick the Portuguese coach tries to use.
"I will never forget that Chelsea game at Anfield when we lost and we were going for the title," Henderson told The Guardian. "It was frustrating for me. I was a fan, I was in the crowd, it was frustrating to watch. I was shouting at the ref to get things going a bit quicker.
"The way they played that game was very clever from Jose. We were on fire at the time and the way they played the game, very slow, sitting in, it was difficult to watch.
"They made it very difficult -- throw ins, goal-kicks, they were taking forever and that got everyone worked up in the stadium and it worked to their advantage because they got the result they came for and it had a big impact on us winning the league.
"I will never really forget that, so Monday will be a big occasion, if we can keep performing the way we are and win, to sort of put that to bed.
"It will be a tough game. United are a good team who have some very good players and a top manager. We need to be ready and prepared for anything that is thrown at us."