Avengers: Endgame - 20 Things We Learned From The Director's Commentary

12. Maria Stark Craving Sauerkraut Is A Very Personal Easter Egg

Tony Stark of course ends up coming face-to-face with his own father, Howard (John Slattery), in 1970, who is bringing home flowers and sauerkraut for his wife Maria, who happens to be pregnant with Tony himself.

Sauerkraut isn't some random pregnancy craving imagined out of nowhere, though: it's a very specific and personal reference for McFeely, whose own mother had the very same craving when pregnant with him.

McFeely calls it "The McFeely Easter egg", appropriately enough.