“Pardon my glasses,” Marisa Tomei said one morning as she sat down for breakfast in an oversize pair of tinted prescription spectacles. “That’s the touch of Aunt May.”

This summer, Ms. Tomei becomes the latest actress to assume the mantle of Aunt May, the kindly guardian of Peter Parker, a nebbishy science student who moonlights as the superhero Spider-Man. In her earliest comic-book appearances, the Aunt May character is presented as a delicate older woman; in previous iterations of the “Spider-Man” movie series, she has been played by Rosemary Harris and by Sally Field.

“Spider-Man: Homecoming,” opening Friday, July 7, reboots the franchise and restores Peter Parker to an adolescent high schooler (played by Tom Holland). A new Aunt May was called for, too. Enter Ms. Tomei, 52, the Academy Award-winning star of “My Cousin Vinny” (and films like “In the Bedroom” and “The Wrestler”), who hopes to put her stamp on the role while respecting the character’s roots. Her Aunt May can be exuberant and quirky, and still sometimes wear her hair in a bun.

“I’m bridging the concepts,” explained Ms. Tomei, who can turn on a dime from gleeful self-deprecation to quiet introspection. “You’ve got to pass the torch.” Ms. Tomei also spoke about sustaining a 30-year acting career, her stint on “Empire” and her Oscars experience. These are edited excerpts from the conversation.