In a large pot, melt the butter over medium heat and add the onions, carrots, celery, garlic and tomato paste. Cook until the onions are soft and translucent, stirring often, about 5 minutes.
Add the flour, and cook for 2 minutes.
Reduce the heat to medium-low, and add the stock, white wine, cognac (or brandy or dry sherry), lobster, paprika and thyme, and stir to combine. Cook for 30 minutes, stirring occasionally.
Stir in the heavy cream, then check for seasoning. If needed season with a little salt and pepper. Remove the sprig of thyme. Serve hot, or if you prefer a smooth bisque, blend the bisque with a hand blender or carefully transfer to a food processor and purée until smooth. Enjoy!