Start by extracting the meat from the lobster shells and set it aside.

In a large saucepan, melt 2 tablespoons of butter over medium heat. Add the lobster shells along with ¼ cup of the chopped onion. Cook this mixture until it becomes fragrant and lightly browned. Pour in the chicken broth and allow it to simmer for 10 minutes while covered. After that, strain the mixture, discarding the shells, and keep the lobster broth.

Next, melt the remaining butter in the same saucepan over medium heat. Add the rest of the onion, carrot, celery, and garlic. Cook until the onion becomes tender. Then, pour in the white wine and sherry, letting it cook down until nearly evaporated. Stir in the Worcestershire sauce and Tabasco, cooking for a few more minutes until it thickens slightly.

Now, add the reserved lobster broth, thyme, bay leaf, and tomato paste. Let it simmer uncovered for 15 minutes or until the bisque thickens. Remove the bay leaf and use an immersion blender to puree the mixture until it's smooth.

Finally, mix in the cream and let it simmer for another 3-5 minutes. Stir in the lobster meat and serve immediately. If you like, garnish with fresh chives for a lovely touch. Enjoy your homemade treat!