A savory jelly based on a fish or meat stock used as relish mould?

The savory jelly you are describing is called aspic.

Aspic is a clear, savory jelly made from a stock (fish or meat) that is thickened with gelatin. It is often used as a base for relishes and molds, where it provides a beautiful, shimmering backdrop for various ingredients.

Here are some key characteristics of aspic:

* Clear and Gelatinous: Aspic is a translucent, slightly wobbly jelly that holds its shape.

* Savory Flavor: It derives its flavor from the stock used to make it, which can be fish, meat, or even vegetable based.

* Versatility: Aspic can be used to create a wide range of dishes, from simple molds with vegetables or meats to more elaborate terrines and galantines.

Aspic is a classic culinary technique that adds elegance and sophistication to any dish.