The Buddies produced a clinical display to end United's run of seven games undefeated - Steven Thompson (2), Paul McGinn and Jason Naismith all on target for the hosts.
Lennon said afterwards: "It was a fantastic result for us. A lot is spoken about the Dundee United youngsters and written about them, and rightly so. But I am delighted with the brilliant crop of youngsters we have.
"None more so than wee McGinn for the composure and finesse that he showed for the second goal. Also the hunger and desire from Naismith for the third goal. Absolutely fantastic.
"The evidence is there that they can go far. The United lads get the credit because of the position they play. They are flair layers who score goals.
"But we have a fantastic conveyor belt here and I'm delighted that they are becoming good impact players."
United counterpart Jackie McNamara added: "The hype hasn't come from us. It has been people watching us.
"The hype is through the media and it is nice to get the recognition but we won't get too carried away. We'll just keep playing the same way. Today we tried it and certain things didn't go for us.
"I'm disappointed to lose the match. A few things went against us. The lads kept at it though and tried to keep playing football and creating chances."