In a large pot, melt 2 tablespoons of butter over medium heat. Add 1 chopped onion and 3 minced garlic cloves, sautéing for about 4–5 minutes until they become translucent and fragrant.

Incorporate 1 cup of crab meat and 1 pound of peeled, deveined shrimp into the pot. Cook for approximately 3–4 minutes until the shrimp turn a light pink.

Pour in 4 cups of fish stock or chicken broth, bringing the mixture to a gentle simmer. Allow it to cook for about 10 minutes.

Gradually stir in 1 cup of heavy cream, seasoning with salt, pepper, and 1 tablespoon of Old Bay seasoning. Let it simmer for another 5 minutes.

Use an immersion blender to puree the mixture for about 30 seconds if you prefer a smooth bisque.

Ladle the warm bisque into bowls, garnishing with fresh herbs like parsley or dill before serving.