Mix the binder: In a bowl, whisk together the mayonnaise, egg, Dijon, Worcestershire, Old Bay, lemon juice, lemon zest, and cayenne until completely smooth. Stir in the bell pepper and parsley. Taste it now, before the crab goes in this is your only real chance to adjust seasoning, and it should taste slightly too assertive on its own.

Chill the binder for 10 minutes: Slide the bowl into the fridge and leave it alone. This is the step that makes or breaks the dish. A room-temperature mayo-and-egg mixture is loose enough to drain off the crab and pool in the dish, which tempts you into adding more binder to compensate and more binder is exactly what turns imperial into casserole. Chilled, it thickens just enough to coat each lump and stay there through the bake.

Fold, don’t stir: Add the cold crab to the cold binder and fold with a rubber spatula using three or four wide sweeps from the bottom of the bowl. Stop while you can still see distinct pieces of crab. Pro tip: if you spot a dry patch, don’t stir again dab a little binder onto it with the spatula tip instead.

Fill and top: Mound the mixture loosely into buttered ramekins or a 1-quart dish. Loose is the operative word; packing it down squeezes out air and gives you a dense, sliceable texture nobody wants. Scatter the Parmesan and panko over the top, drizzle with melted butter, and dust with paprika and a pinch more Old Bay.

Bake until just set: Place the ramekins on a sheet pan and bake at 375°F for 20 to 25 minutes, until the top is golden and the center reaches 155–160°F on an instant-read thermometer. The edges should bubble gently. If the top hasn’t browned to your liking, run it under the broiler for 60 to 90 seconds and stand there watching it.

Rest, then serve: Let it sit for 5 minutes before serving. The binder firms slightly as it cools, and a spoonful will hold its shape instead of sliding across the plate. Serve with lemon wedges.