crab stock has very strong flavour if made correctly.
i start by roasting the shells in an oven rather than in a pan.
then sweat down your miripoix with red chillies, red peppers, ginger, fennel and an orange.
deglaze with white wine, vermouth and brandy, add cold water and tomato paste and simmer very gently for a few hours.
if you have any fish bones such as halibut of monkfish or skate soak them for an hour in water to remove any blood
and add to the stock for the last 20 mins.
make a bouquet garni with star anise, coriander seeds, caraway seeds, fennel seeds or anything aromatic you can find and leave to infuse over night
i use this stock to make amazing risottos or reduce it by 90% and finish with cream for a rich sauce.
or if you really want to go crazy you can then cook crabs in the stock rather than in court boullion and get extra crab flavoured crabs and the stock will get stronger