Start with fresh blue crabs from Chesapeake Bay in Maryland. They can vary in sizes but most of them weight less than a pound each, between maybe 8 - 10 oz. Start off by cleaning the crabs under running cold water and (this is not for the faint of heart) chopping the all crabs into half. Save all the juices and bits and pieces of the crab guts that may have accidentally fallen out. These are the yummy parts that will bring the entire dish together when cooked.
Next, prepare the spice mix by grinding them in a food processor. The mix include:
1 TBP fermented soy bean paste
2 inches fresh ginger (grated or chopped fine)
3 - 5 cloves of garlic
2 stalks of lemongrass
5 oz. shallots
Chillis (if you so choose)
Also, at this point, prepare some tamarind juice by soaking the tamarind pulp in hot water for about 10 minutes and straining it to remove all the impurities.
Now let's get the wok going and heat up about 2 TBPs of canola oil. Add the spice mix into the wok and stir-fry until fragrant. Add 1 teaspoon of coriander powder together with 1 TBP sugar. Next, add the chopped crabs along with 1/4 cups of water and 3 TBP of the tamarind juice that was prepared earlier. Stir, bring the heat down to a simmer and cover the wok for 3 - 5 minutes in order to cook the crabs, juices and all. Taste the sauce and adjust by adding salt and pepper or more sugar. Just before serving, add in chopped Chinese chives or scallions (either will do) and continue stirring. It is now ready to eat. Dig in!