Make the Seafood Stock:

• Heat olive oil in a large pot over medium heat. Add the shrimp shells and sauté until they turn pink and fragrant, about 5 minutes.
• Add 4 cups of water and bring to a boil. Reduce heat and simmer for 20 minutes. Strain the stock, discarding the shells, and set aside.

Cook the Vegetables:

• In the same pot, melt butter over medium heat. Add chopped onion, carrots, and celery. Cook until the vegetables are soft, about 8-10 minutes.
• Add minced garlic and cook for another 2 minutes.

Create the Base:

• Stir in the tomato paste and cook for 2 minutes, until it deepens in color.
• Sprinkle flour over the vegetables, stirring constantly to create a roux. Cook for 2-3 minutes to remove the raw flour taste.

Add Liquids and Blend:

• Gradually whisk in the seafood stock and bring to a simmer. Add the bay leaf, paprika, salt, and pepper. Simmer for 15 minutes to meld the flavors.
• Remove the bay leaf. Add the shrimp to the pot and cook for about 3-4 minutes until they turn pink and opaque.
• Use an immersion blender to blend the soup until smooth. If using a regular blender, carefully blend in batches with hot liquids.

Finish the Bisque:

• Stir in the heavy cream and dry sherry. Taste and adjust seasoning as needed. Let the bisque simmer for a few more minutes to combine the flavors.

Serve:

• Ladle the bisque into bowls, garnish with chopped parsley, and serve hot.