The Hoops dominated proceedings at Celtic Park, but County had the best two chances of the opening half before Scott Brown and substitute James Forrest struck either side of a Gary Hooper brace after the break.
"I am delighted, thrilled with the performance, it was a good home win which was coming," Lennon said. "We were excellent, particularly in the second-half
"I wasn't too unhappy with the first-half but we got a clean sheet and four goals and that is our fifth win in a row now so we are starting to pick up the pace."
Forrest made his first appearance since October, following a hamstring problem, and the winger caused a moment of concern for the Celtic manger when he pulled up because of gluteus maximus.
Lennon added: "He felt his glute towards the end so we are keeping an eye on that but it is great to have him back.
"If we lost him for a length of time again it would be devastating for us because of the wonderful talent that he is.
"He knows he has to report any extra niggles straight away so we are going to monitor him very carefully and make sure his is fit and ready for the games.
"He has worked really hard the last six, seven weeks and you can see his in great shape and great condition and we just need to get him on the pitch."