2,328. Cooking an Animal's Heart

Maachalos Assuros 6:6

If someone wants to roast or cook a heart, he must first cut it open, remove the blood, and salt it. If one cooks a heart without cutting it open, one may do so after cooking and it is then permitted; if he eats it without cutting it open, he isn’t liable to kareis. This is the case regarding a bird’s heart, which doesn’t contain an olive-sized volume of blood. If one eats an animal’s heart without cutting it open, he is liable to kareis because there’s an olive’s volume of blood in the heart.

Maachalos Assuros 6:7

If one cuts open an animal’s liver and throws it into vinegar or boiling water until it turns white, it may be cooked afterwards. The universally accepted Jewish practice has become to broil it over fire and then to cook it, either alone or with other meat. Similarly, the common practice is that brains aren’t cooked or roasted until they have been broiled with fire.