Spread the bread in a single layer on a rimmed baking sheet and bake for 10 minutes, until lightly toasted. Let cool to room temperature. Leave oven on.
Add the toasted bread to a food processor and pulse until finely ground. You should have about 4 cups of bread crumbs.
In a large bowl, combine the bread crumbs, 4 tablespoons of melted butter, the cheddar cheese, and 1 teaspoon of salt and toss to combine. Set aside.
In a medium pot, combine 4 cups of white wine and a generous pinch of salt and bring to a boil over medium high heat. Add the shrimp and cook until bright pink, about 1 minute. Use a spider or slotted spoon to transfer the shrimp to a colander to drain.
Return the wine to a boil. Add the scallops and cook until just opaque, about 2 minutes. Transfer the scallops to a colander to drain.
Chop the shrimp and scallops into bite size pieces. Transfer to a large bowl, along with the crap and 1 teaspoon of salt. Toss to combine.
In a liquid measuring cup or medium bowl, whisk together the half-and-half, 3 tablespoons of melted butter, the flour, Worcestershire sauce, paprika, lemon juice, ketchup, remaining tablespoon of white wine, and remaining teaspoon of salt.
Brush the remaining tablespoon of melted butter in a 9 by 13 inch baking dish.
Scatter the artichokes in an even layer over the bottom of the baking dish. Scoop the seafood mixture over the artichokes. Pour the sauce over the bread seafood. Top with the bread crumb mixture.
Bake the casserole for 20-25 minutes or until bubbling and golden brown.
Top with chives and serve with lemon wedges.
Enjoy!
Using a standard milk instead of half-and-half will cause the cream sauce to break when combined with the acidity of the lemon juice and white wine, leaving a watery residue at the base of the dish. Half-and-half provides a 10.5 to 18 percent butterfat content that stabilizes flour thickeners under sustained oven heat, protecting the dairy from curdling at 350 degrees. Swapping out the sourdough loaf for pre-ground grocery store bread crumbs changes the moisture absorption rate entirely; industrial crumbs lack the irregular crumb structure needed to absorb excess liquid from the artichoke hearts and seafood. Toasting the torn sourdough pieces for exactly 10 minutes drives out internal moisture so the bread can rehydrate evenly with melted butter without turning into paste during the 20 to 25 minute bake time. Poaching the shrimp and scallops in boiling white wine rather than water infuses the delicate proteins with organic acids that brighten the natural sweetness of the shellfish. Removing the shrimp precisely at 1 minute prevents the proteins from tightening past the point of tenderness, keeping them resilient even after a secondary round of cooking in the oven. Cutting the poached shrimp and scallops into uniform bite-sized pieces ensures that each scoop of the finished dish distributes the expensive crabmeat and tender mollusks proportionally. Canned artichoke hearts must be drained thoroughly and pressed in a clean kitchen towel to eliminate surface moisture that would otherwise dilute the half-and-half sauce. Chilled portions store safely in an airtight container for up to three days, though the toasted sourdough topping will lose its crisp texture upon reheating. Restoring that initial crunch requires pulling the casserole from storage, scraping away the softened bread crumbs, and replacing them with a fresh batch of toasted sourdough before warming the dish through.