The 20-year old Frenchman netted the Reds second goal in injury time to see off United at Anfield, describing it as one of the best moments of his career.
"This was a fantastic moment for me and the team and I would say it's my best moment in football," N'Gog said.
The former Paris Saint-Germain man said the goal meant so much to him and the win meant even more.
"I dedicate this goal to my family who always support me and the Liverpool supporters. We know how much this victory means to our supporters," he added.
"I also give thanks to my teammates and the manager for always showing faith in me.
"We know we have a lot of quality so this result means everything for the team.
"We have worked really hard together and I think we deserved to win."