Finely dice the onion, celery, and carrots to create a classic mirepoix.
In a large pot, melt the ghee over medium heat and sauté the onion, celery, and carrots until softened and translucent, about 8 minutes.
Stir in the minced garlic, tomato paste, dried thyme, sea salt, and black pepper, cooking for 2 minutes until the paste turns a deep brick red.
Pour in the dry sherry to deglaze the pan, scraping up any browned bits from the bottom.
Add the seafood stock and bring the mixture to a gentle simmer for 15 minutes.
Using an immersion blender, process the soup base until completely smooth and velvety.
Stir in the heavy cream and the cooked lobster meat, heating through for 3-5 minutes without reaching a boil.
Ladle the bisque into bowls and garnish with finely chopped fresh chives before serving.