In the few weeks since he passed for 384 yards and six touchdowns in his first career start, Lark, who waited a lifetime to be the Cougars' starter after being buried on the depth chart for years, has suddenly become a celebrity of sorts.
His Twitter account mushroomed from 40 followers to 1,100 almost overnight. When he goes around town, people recognize him and want to talk to him. The other day, a stranger approached Lark and his wife at Costco and complimented him on his play.
"That kind of comes with the position," Lark said. "It's happened quite a few places. It's kind of humbling. I've always wanted to be the starting quarterback at BYU, and getting that chance was such a great opportunity and so fun. People have been so good to me about it, and I've been grateful."
Not that he takes all the credit for his performance.
"I saw a stat a few days after that there was not one drop by a wide receiver that game. I couldn't be more happy and proud of my teammates," Lark said. "They made it so easy on me. Some of them were wide-open, but a lot of them made great plays. I was grateful to them."
Lark, 25, is preparing for his final collegiate game when the Cougars face San Diego State in the Poinsettia Bowl on Dec. 20. It's too early to know if he will get one more start, one last chance for an encore.
This week, Lark took the majority of snaps in practices while fellow senior Riley Nelson continues to nurse a rib injury. Coach Bronco Mendenhall said he likely won't name a starter until game day.
Of course, Lark is taking it all in stride. "Whatever happens, happens," he said.
Lark's story has been chronicled before. The highly recruited QB arrived at BYU in 2006 after throwing for 6,739 yards at Pine View High in St. George. He served a mission for The Church of Jesus Christ of Latter-day Saints in St. Petersburg, Russia, then slipped quietly into anonymity, playing behind Jake Heaps, Nelson and even freshman Taysom Hill.
But Lark kept working hard in the face of the many disappointments. To start, and to play well, against New Mexico State was rewarding for him. He called it a "dream come true" after the 50-14 win.
Regardless of what happens in the bowl game, Lark said his time at BYU has been "completely worth it. I had a lot of frustrating times. Sometimes there were sleepless nights when I was so upset and frustrated. But in the end, it's given me so much more than just football. My life has been so blessed because of the experiences I've had here."
Lark credits his missionary service for helping him cope with the setbacks in football. The lessons he's learned during his Cougar career transcend the sport.
"I bring a little bit of my beliefs into this. I think God teaches us different things at different times in our lives," he said. "He taught me a lot of things on my mission that I didn't have to relearn. He was able to teach me new things from all these experiences. A lot of the things I learned on my mission, he would have had to teach me during football. The mission put me ahead in a lot of areas in maturity and things like that. It's made me a better person."
Because he started the season as the backup, and the fact that he's a senior, Lark said this season has been the toughest of all, up until his first start.
"Each year is a little harder because you put that much more effort into it. This year was the closest it came (to starting). The letdowns were a lot bigger than in the past. There were some frustrations, but it was all worth it to get that one start and hopefully I get another chance to play. I don't know. But I'll be ready."
Lark and Nelson are close friends and they've been supportive of each other. For years, they've been roommates when they've traveled to road games, and they've sat together in countless team meetings.
But only one of them can start the Poinsettia Bowl.
"If he's called upon, or if I'm called upon, I feel confident that we'll be able to execute the game plan and give ourselves a chance to win," Nelson said.
In Las Cruces, N.M., Nelson stood on the sidelines and watched Lark turn in one of the best passing performances at BYU in years.
"To see him get to showcase what he can do and to be so prepared and play so well with the opportunity that he got, I'm glad it turned out that way for him," Nelson said. "I'm happy for him."
Offensive coordinator Brandon Doman, who took over as a starter toward the end of his junior season as BYU's quarterback before starting as a senior, said he understands what Lark has been through.
"Unfortunately, mine happened when I was a junior, and his happened as a senior," Doman said. "He's been loyal and he's a great friend and I couldn't be more happy for him."
And Doman liked watching Lark excel in his first start. "I was so proud of him," he said. "I couldn't have been more pleased for how he did."