Place crab shells in a medium stockpot with water, white wine, quartered onion, chopped carrot, chopped celery, bay leaf, peppercorns and 1 tsp salt. Bring to a simmer over medium heat, reduce to low and simmer gently, uncovered, for 30 minutes. Do not boil hard — a gentle simmer extracts flavor without bitterness.

Strain the stock through a fine-mesh sieve into a bowl, pressing on solids to extract liquid. Discard solids and set the stock aside. Measure 4 cups for the bisque recipe; refrigerate or freeze any excess.

Base & Mirepoix

Sweat vegetables

In a heavy 4–5 quart pot, heat butter and olive oil over medium heat until butter is foaming. Add diced onion, celery and carrot and cook gently, stirring, until vegetables are soft and translucent, about 6–8 minutes. Add minced garlic and cook 30–45 seconds until fragrant.

Build roux

Stir in tomato paste and cook 1–2 minutes to remove raw tomato flavor. Sprinkle in the flour and cook, stirring constantly for 2–3 minutes to cook out the raw flour taste and form a blond roux (should be slightly golden but not brown).

Combine & Simmer

Slowly whisk in 4 cups of the prepared crab stock, preventing lumps. Increase heat to medium and bring the mixture to a gentle simmer, stirring frequently to thicken slightly. Simmer for 8–10 minutes to marry flavors and cook the flour.

Stir in milk and simmer 3–4 minutes, then add heavy cream and dry sherry. Reduce heat to low and simmer gently for another 6–8 minutes—do not boil aggressively to avoid splitting the cream.

Finish with Crab

Taste the soup and season with Old Bay, Worcestershire sauce, hot sauce (if using), lemon juice, additional 1 tsp salt and 1/2 tsp freshly ground black pepper. Adjust to taste. Remove from heat.

Fold in the lump crab meat gently so it doesn’t break up too much. Allow the soup to sit off heat for 2–3 minutes so crab warms through. If you prefer a smoother bisque, reserve about 1 cup of the soup and puree with an immersion blender or transfer to a blender, then stir the puree back into the pot for a creamier texture while still keeping pieces of crab.

Stir in chopped parsley and most of the chives, reserving a little for garnish.

Serve & Garnish

Ladle bisque into warmed bowls. Top each bowl with additional lump crab meat (if using), a drizzle of warmed clarified butter, a sprinkle of chopped parsley and chives, and croutons or toasted brioche on the side or floated on top.

Serve immediately with lemon wedges and extra hot sauce on the side, if desired.