Fill a large bowl with ice and cold water, and set it aside.

In a 6 quart cast iron Dutch-oven, or other heavy-bottomed pot with a tight-fitting lid, combine the tomatoes, wine, water, sliced onions, peppercorns, tarragon, and bay leaf. Bring to a boil over high heat, reduce the heat to a simmer, and cook for  15 minutes.

Raise the heat back to high. Add the lobsters to the pot, one at a time, cover the pot immediately with a tight fitting lid. Steam the lobster until they are bright red and you can pull the long feelers on the head out with no resistance, about 9 to 11 minutes. Using tongs, immediately plunge the lobsters into the bowl of ice water and let cool for 5 minutes.  Repeat with the remaining lobsters.

Remove the lobsters from the ice water and set on a rimmed baking sheet. Using kitchen shears, remove the lobster meat from the tail and claws. Use a knife to chop the meat into bite size pieces. You should have about 2 cups of lobster meat, set aside until ready to use. Best if eaten in 2 days.

Rinse the lobster shells and reserve to make stock.