There are more socially acceptable opportunities to eat a cake than to destroy a cake. Knock it on the floor and if it’s their home, grind the remains into the floor. If you really want eat some of the cake, you can knock down the cake with an open hand, eat that handful and then wipe your hand on their wall, curtains, or face.

But I dunno. If someone these days is making a problematic cake, I don’t trust them to cook with safe ingredients or techniques.