The Oscar winner has portrayed comic book character Pepper Potts in seven films in the Marvel Cinematic Universe since 2008's "Iron Man", including the 2017 movie about the web-slinging crime fighter.
But Gwyneth's appearance as Potts at the end of "Homecoming" was so brief that she had to be reminded of the shoot by her co-star and "Iron Man" director Jon Favreau during a recent chat on his new Netflix series, "The Chef Show".
Now Tom, who reprises his role as the titular superhero in latest instalment "Spider-Man: Far From Home, has admitted Gwyneth's poor memory had left him shaken.
"I mean, I've only worked with Gwyneth one time, on 'Spider-Man: Homecoming', which she doesn't remember. Which still to this day breaks my heart," he said during an interview with PopSugar.
Tom then corrected himself, as he remembered one other instance of working with the actress - on "Avengers: Endgame".
"No, actually no, that's not true," he added. "One time when we were shooting 'Endgame', she was in her blue suit, and I was in my Spider-Man suit, and she came up and she asked me for a photo with me and Robert (Downey, Jr.) And I think she posted it and she said, 'Robert Downey Jr. and myself and this guy'. I was just the guy. It was cute."