This dish, often served in a clay pot, is characterized by its rich, creamy tomato-based gravy, subtly sweet with a hint of smokiness, and features a particular black lentil as its key ingredient.

1. It's a staple at most Indian restaurants.
2. The key ingredient is a type of lentil that is black.
3. The preparation involves slow cooking for hours to achieve a creamy texture.
4. It is often finished with a dollop of butter or cream.