Lobster bisque

There are two things I usually have to try at a restaurant. One is bread pudding. The other is lobster bisque. Though I am much picker about where I order my lobster bisque from (no Red Lobster version for me).
Lobster has come down in price as of late (at least in my area) and so I thought I would make a bowl of it for myself at home. There is some work involved, especially since you make your own stock but it gives it a nice flavor.

Lobster Bisque

2 cloves garlic, chopped
1 shallot, chopped
1 stalk celery, chopped
2 tsp tomato paste
8 ounces unsalted butter
1-1/2 lbs Maine lobster
32 ounces water
2 cups heavy cream
2 bay leaves
? cup dry sherry
Salt and pepper to taste

Instructions:
Steam lobster in water until done, about 8 minutes. Save stock. Remove lobster meat from shell; set aside. Break up lobster shells, then place them back into the water; simmer over low heat until reduced by half.
Heat half the butter in a pan over medium heat. Add shallots, garlic and celery and saute until soft, about 10 minutes.
Add bay leaf, tomato paste and sherry and simmer for 10 minutes or until reduced by half.
Add cream and lobster stock and simmer over low heat (Do not boil.) for 30 to 40 minutes or until soup begins to thicken.
Season with salt and pepper. Remove lobster shells and bay leaves. Chop up lobster meat and add to bisque. Stir in remaining butter.
Serve hot with a little cr?me fraiche and fresh chives.