Hansbrough scored 17 points in the first 20 minutes, and sixth-man sensation Danny Green added 14 in the opening stanza to keep the Ivy League's Quakers from getting too close to the nation's top-ranked team.
The Tar Heels regained their composure at halftime, and used an early 15-6 run to break open the game held at the historic Palestra, which has hosted more games, more visiting teams and more NCAA tournaments than any other facility in the nation.
"I thought early in the second half we were really good," UNC head coach Roy Williams said. "Offensively, we were effective. We were making shots, we were getting some steals and going down on the break. They missed a couple – when it's a 13-point game, if we don't do that and they make a couple, then all of sudden it's in single digits."
Despite being the biggest player on the court for most of the evening, Hansbrough outran everyone on two occasions for breakaway dunks, including a two-handed slam that put the Heels up 77-53 with 11:45 remaining.
"I think I just got some good post-ups," Hansbrough said about his performance. "I think I put myself in better positions at times… and things just went my way."
North Carolina took the floor against Penn with more talent and more experience, and it especially showed on the offensive end of the floor with the Tar Heels shooting 57.3 (43-of-75) percent on the night.
But the defensive effort left plenty to be desired as the Quakers shot 47.6 percent (30-of-63 from the floor, 3-of-19 on three-point attempts) despite turning the ball over 22 times. Freshman Tyler Bernardini led Penn with 26 points of 10-of-17 shooting.
"We didn't do a very good job of holding them down," Williams said. "Our defense I was not very pleased with. In the second half, they just missed some shots. Our whole thing is that we know that we're going to give up a couple of backdoor lay-ups, but we still want to get out there and pressure and try not to give up [three-point shots]."
Wayne Ellington's homecoming game brought out some anxious moments early for the sophomore guard, who finished with 13 points on 5-of-14 shooting.
"There was a little pressure coming in and playing in front of your family and friends, but you get over it and just have to get into the flow of the game," Ellington said.
Ty Lawson chipped in 14 points, while Deon Thompson posted a double-double with 12 points and 10 rebounds in helping the Tar Heels win the rebounding battle, 46-21.
The smaller and less talented Penn squad outhustled the Tar Heels in the early going of Tuesday's contest, scoring easy baskets on backdoor cuts and feeding off the Palestra's sellout crowd of 8,722 to shoot 56.7 percent from the field (17-of-30) in the first half, despite connecting on just 2-of-10 three-pointers. But North Carolina's advantages in rebounding (21-14) and forced turnovers (14-7), as well as Hansbrough and Green's combined 31 points, were plenty enough to give UNC a 50-37 halftime margin.
The Tar Heels are 8-0 for the first time since the 1998-99 season. They'll head back to Chapel Hill and break from basketball for final exams, before heading back up the East Coast for a Dec. 16 game at Rutgers -- the final leg of UNC's six-straight games away from the Smith Center.