Marc Solis, after a 23-year teaching career, is ready to retire. He told me this over the phone as he trimmed briskets during his lunch break from Heights Elementary School in Laredo, where he teaches special education students. The ten-minute walk to LowPoint Barbecue from the school has become a weekday routine since he opened the restaurant in 2023. “I can’t serve two masters,” Solis told me. To become the pitmaster he hopes to be, Solis needs to make barbecue his full-time job. “I’m going to be taking the plunge,” he said.Solis has been taking steps to get here since 2020. He taught his students virtually during the pandemic and used his extra time to work on his backyard smoking skills. In 2022, he got…