1) Heat 1 cup milk, not to boiling.
2) Add 4 tablespoons vinegar. Stir for a few minutes.
3) Strain out curds. Squeeze to remove as much liquid as possible.
4) Form into a shape or press into a mold, let dry.
It's in that small category of objects that seems like plastic, but are still edible. Tastes bad, though.There was a variation of this in a midcentury science book for a children that I'd check out from the library as a kid. It was used to demonstrate how to make your own 'plastic' action figures.
That's literally a recipe for paneer cheese. Tastes awesome fried and mixed into many Indian dishes.