Creamy Crab and Shrimp Seafood Bisque

Sauté the Aromatics: In a large pot or Dutch oven, melt the butter over medium heat. Add the onion, garlic, celery, and carrot and cook until softened, about 5-7 minutes.
Make a Roux: Stir in the all-purpose flour and cook for 1-2 minutes, stirring constantly, until the flour is lightly golden. This creates a roux, which will help thicken the bisque.
Add Liquids and Flavorings: Gradually whisk in the seafood or chicken broth to avoid lumps. Stir in the tomato paste, Old Bay seasoning, salt, pepper, and cayenne pepper (if using). Bring to a simmer.
Simmer and Blend: Reduce the heat to low, cover, and simmer for 15-20 minutes to allow the flavors to meld.
Puree the Soup: Use an immersion blender to puree the soup until smooth. Alternatively, you can carefully transfer the soup to a regular blender in batches and blend until smooth (be cautious when blending hot liquids!). Return the pureed soup to the pot.
Add Seafood and Cream: Stir in the shrimp and crab meat. If using sherry, add it now. Cook for 3-5 minutes, or until the shrimp is pink and cooked through and the crab is heated through.
Finish the Bisque: Stir in the heavy cream and heat gently, being careful not to boil. Taste and adjust seasonings as needed.
Serve: Ladle the bisque into bowls and garnish with fresh parsley. Serve with lemon wedges on the side.
Tips and Variations: