Melt butter in a large heavy-bottomed pot or Dutch oven over medium heat. Add onion and celery, cooking for 5-6 minutes until softened and translucent.

Add garlic and cook for 1 minute until fragrant. Sprinkle flour over the vegetables and stir constantly for 2 minutes to cook out the raw flour taste.

Slowly pour in the seafood stock while whisking constantly to prevent lumps. Bring to a gentle simmer.

Add whole milk, Worcestershire sauce, Old Bay seasoning, cayenne pepper, and AP Seasoning. Stir to combine and simmer on low for 20 minutes, stirring occasionally.

In a small bowl, whisk egg yolks with heavy cream. Temper by slowly adding a ladle of hot soup to the egg mixture while whisking, then pour the tempered mixture back into the pot.

Gently fold in the lump crab meat, being careful not to break up the pieces. Cook on low heat for 10 minutes. Do not boil.

Stir in dry sherry and fresh lemon juice. Season with salt and black pepper to taste.

Simmer for an additional 5 minutes on the lowest heat setting to let flavors meld.

Ladle into bowls and garnish with fresh chives and an extra pinch of Old Bay. Serve with crusty bread.