Lobster à l'américaine

1/Store the lobsters during 15 minutes into the deep freezer to make them be insensitive to pain and thereafter cut them very quickly : hold the lobsters (one after the other) firmly, cut the claws at the thorax level with a big knife, then hit the claws strongly with the flat side of the blade to break them. Then cut the tail into 6 slices at the level of the rings, then cut the thorax into 2 halfes (left and right sides).
Get rid of the stony pouch which is in the head and using a spoon, remove the greenish creamy part of the center of the body (called "coral") and keep it in a small bowl.
2/Heat the olive oil in a quite large sauce pan and when the oil is smoking, put into it the lobster pieces, season with salt and black pepper and remove them when they have become red with a skimmer and put them onto a plate.
3/In the same (uncleaned) sauce pan very gently cook the onions and the shallots untill they melt, then add the tomatoe tomatoe, stir well and after 2 minutes, add the wine, the fish stock (or the equivalent quantity of water), the brandy, the tomatoes, the tarragon, some salt and a pinch of semi hot red pepper in powder.
4/Add the lobster pieces into the sauce pan (the juice should just cover the lobsters) and gently cook during 25 minutes.
5/Remove carefully the lobster pieces with a skimmer and keep them into a deep sauce pan.
6/Add the butter (that must be creamy) to the lobster coral with the brandy for the sauce and the flour and mix with a spatula. Pour it into the sauce, stir well with a whip and blend it. Make it boiling and slightly thickening, then add the chervil and sieve the sauce on the lobster pieces. Adjust the seasoning and serve this lobster "à l'américaine" with plain white pilaw rice