Heat 2 tablespoons butter in a heavy 2 quart saucepan.  Add onions, garlic, shallots and lemon grass and sauté until onions are slightly translucent. Add curry paste and cook about 1 minute until aromatic. 

Add asparagus and coconut milk and bring mixture to a simmer. Cook for about 30 minutes until asparagus is tender.  Remove from heat.  Working in batches add soup to beaker of a food processor and process until smooth.
Return to pan.  Add cream and lemon juice and warm through.  Taste and adjust seasonings as needed.

Prepare Lobster Garnish
Heat butter in heavy skillet.  Add shallot and tarragon and cook until shallots are tender.  Add lobster and toss lightly in butter, shallot mixture until lobster is heated through.

To Serve
Divide the lobster mixture evenly between 6 wide, shallow bowls placing it in the center of each bowl.  Ladle soup into each bowl around lobster.

Pacific 'O
Pacific'O - Official website for Pacifc'O Restaurant located in Maui, Hawaii