The NCAA doesn't officially track the fastest time for two touchdowns to start a game, but notable examples include Auburn's 2:13 against Alabama A&M in 2024 (34-yard run at 0:47 elapsed, 67-yard pass at 2:13). Today's Texas Tech vs. Oklahoma State game saw two TDs in 2:04 (99-yard kickoff return at 0:14, 26-yard pass at 2:04). If there's a faster one, it's likely under 2 minutes, but I couldn't find confirmation.