Mini Castevet Eating Cake In Rosemary's Baby (1968)

Horrific table manners...the lot of them...commencing to eat before everyone is served, and then plowing into it like pigs at a trough! Tsk, Tsk

And shouldn't Minnie have served Devil's Food Cake?

I think Ruth Gordon performed that scene the way she did because the cake was supposed to have some kind of "potion" in it to assist in making Rosemary's baby the devil, and Ruth was anxious about making sure Rosemary ate it.

Plus, the grotesquerie of the eating supported the notion that the Castevets were evil and barbaric.

She just looks like somebody from the great depression eating fast because the food might go away quickly

That cake looks like something she picked up at Costco.

Of course Guy would be talking about his acting career, his characters, and the way he interpreted them, as most actors would.

Minnie eats like a savage, her eyes scanning the table (seemingly to see who needs another slice of cake, but also noticing every detail), and this helps distract the audience from Roman’s easy manipulation of self-centered Guy. (“I loved your performance as Deacon #5 in Luther. You did some little gesture, what was it? So meaningful.”)

Guy agrees to let Minnie and Roman impregnate Rosemary to help his own career. The way Guy and Minnie attack the cake shows how greedy they are - Minnie for a devil child, Guy for a successful acting career - while Guy’s interaction with Roman shows Guy as weak-minded and easily led.

That was a performance that won an Academy Award. But it was also way, way OTT. She was trying to steal every scene she was in.

And soon Rosemary would adopt their eating style as she sears a steak for all of 3 seconds on each side before chowing down....

She stole every scene she was in without trying.

Similar to R3 I imagined her growing up in a large, hungry family and eating defensively

It's the only way to eat Satanism Cake, OP.

Stab! Shove! Chomp! and then scan the table not just with her eyes but with her entire upper torso.