The American is back at the TPC at Summerlin, a year after winning his fourth PGA Tour title with a six-stroke victory.
Simpson, 29, said it was a tournament he enjoyed coming back to, having had a two-week break after the United States' poor Ryder Cup outing.
"It's great to be back. I love coming here, it's always great weather as we're going to see again this week I believe," he said.
"I think I love this golf course because it reminds me of the course I grew up playing. You have a lot of options off the tee and the greens are undulating and fast.
"So, I'm just comfortable here, comfortable playing this kind of golf. I feel good I've had two weeks off after the Ryder Cup and rested up."
Simpson, the 2012 US Open champion, finished six shots clear at the tournament in October last year.
According to Simpson, he "maxed out" with his performances in every round.
"It was one of those weeks as well where every day I kind of maxed out what I got out of the round and normally to win a tournament you need two or three of those, but I did it every day," he said.
"The main thing is I made a lot of putts and you've got to do that this week.
"There's three par fives all reachable and a reachable par four so you really have to take advantage of the short holes and make putts."