Sitting alongside Robert Downey Jr, Tom Hiddleston, Mark Ruffalo, Jeremy Renner and Chris Hemsworth, the actress complained that her co-stars were getting all the existential questions, while hers was a bit more basic - how she got to fit into her skintight catsuit to play the Black Widow.
"How come I get the rabbit food question?" she asked.
But she went on, "Yes, surely. You're training and doing all that stunt work so you eat a lot of green things."
Johansson is taking the same role she played in Iron Man 2, for this big-budget adventure which sees Marvel's superheroes Iron Man, Thor, Loki, The Incredible Hulk, Captain America, the Black Widow and Hawkeye all come together to fight... peril (no spoilers, everyone in the room promised today).
Johansson as Widow and Renner as Hawkeye have no superhero skills in comparison with their peers, but the actress said she liked that - "those powers can go."
And she explained that their roles, along with that of Loki played by Tom Hiddleston, required spending many more hours in the stunt gym than the others - "we have these huge, intense choreographed sequences... those hours in the stunt gym, we became like a family.
"I'm happy to do that. It's great fun to do it. We all have our burden to bear, but certainly the stunts paid off in the end."
As for playing a strong female character, the star of The Other Boleyn Girl and Lost In Translation, remarked that director Joss Whedon had appeared almost "gender-blind" when talking to her about the role:
"He wants his female characters to be dynamic, competitive, assured and confident and that has nothing to do with anything but the fact that he celebrates those kinds of strong female characters."
The film is in UK cinemas from 26 April. The stars were on the red carpet at London Westfield this evening for the European premiere...