Melt the Butter: In a large pot, melt the butter over medium heat. Add the chopped onion and minced garlic, sautéing until the onion is translucent and fragrant, about 5 minutes.

Simmer the Broth: Pour in the seafood or vegetable broth, bringing it to a gentle simmer.

Add the Seafood: Stir in the crab meat, shrimp, Old Bay seasoning, salt, and pepper. Cook until the shrimp turn pink and are fully cooked, roughly 5-7 minutes.

Incorporate the Cream: Lower the heat and gently stir in the heavy cream. Warm it through but be careful not to let it boil.

Serve and Garnish: Ladle the bisque into bowls, garnishing with chopped parsley.