1Begin by cooking the lobsters in boiling water for about 8-10 minutes until they are bright red. Remove them from the pot and let them cool.
Once cooled, remove the meat from the shells and set it aside. Reserve the shells for later use.
In a large pot, melt the butter over medium heat. Add the chopped onion and minced garlic, and sauté until the onion is translucent.
Stir in the flour and cook for about 2 minutes, stirring constantly.
Add the brandy and white wine to the pot, and cook for another 2 minutes to allow the alcohol to evaporate.
Add the seafood stock, diced tomatoes, and reserved lobster shells to the pot. Bring to a boil, then reduce the heat and let it simmer for 30 minutes.
Remove the lobster shells from the pot and discard them.
Use an immersion blender to puree the soup until smooth. Alternatively, you can transfer the soup to a blender in batches and blend until smooth.
Return the soup to the pot and stir in the heavy cream. Add salt and pepper to taste.
Add the reserved lobster meat to the soup and heat through.
Serve the lobster bisque hot, garnished with additional cream or herbs if desired.