Who would have known that Arya's run-in with Hot Pie would give her all the information she needed, as far as knowing where her remaining family members are? But when she stopped at his inn for some free lunch on her road trip, he filled her in, leading some fans to ask, who is Hot Pie on Game of Thrones? Arya reunited with her friend from earlier in the series, and he's honestly as sweet as ever.
Back in Season 2, when Arya was on the run and posing as a boy, she developed a friendship with a few of the other kids who were eventually recruited to join the Night's Watch. This was also when she and Gendry (Robert Baratheon's last remaining bastard) became BFFs, but he's still M.I.A., and that's too painful to even talk about.
Hot Pie, on the other hand, was a learned baker. Curiously enough, that was his biggest passion as an orphaned kid on the road with slave traders. He evidently kept up with it, as Brienne and Podrick came upon the inn where he works back in Season 4. Last time, he was able to give them game-changing news, and he told them he'd last heard that Arya was traveling with the Hound. And on this episode, when Arya and Hot Pie reunited on Game of Thrones, he did the same.
Hot Pie works at an inn where tons of soldiers and knights pass through on a daily basis, so he presumably hears things. But he basically filled Arya in on everything she missed about Jon in the North. It's what prompted her to change course and head to Winterfell instead of King's Landing, so she might cross paths with Jon or, at the very least, arrive home in time to help Sansa run things and allow her to be reunited with her family for the first time in a very long time.
I don't know if we'll ever see Hot Pie again on Game of Thrones, but once more he managed to help the Starks along, even if he didn't realize how much help he was to them. This also, unfortunately, means that Arya's going to have to put a hold on killing the queen, but it's for a good cause. Hot Pie will never know what a service he's done for the Seven Kingdoms. And I'm not just talking about his bread and kidney pies.