Well, contrary to Susan's taste, I like domestic goose fat - but not a goose swimming in it. Before you even stick it in the pan, look for obvious loose fat deposits (around the openings) and remove them. Roast goose on rack as suggested - I like to flavour mine with apples, quartered.

Now, discard goose (kidding, the goose will taste great): drain the liquid fat from the goose pan through a seive into a container. It will cool to a solid white grease. This fat will be clean, faintly taste of apple, and makes fantastic fluffy biscuits. And is a good hand softener, especially on winter rough skin.

I once got three litres of fat off a single five kilo goose.