Preheat oven to 375°F (190°C). Thoroughly pick through the crab meat to remove any shell pieces. Drain canned artichoke quarters and roughly chop into 1/4–1/2-inch pieces. Mince garlic and finely chop parsley.

Mix base

In a large mixing bowl, beat the room-temperature cream cheese with a whisk or spatula until smooth. Add mayonnaise, sour cream, Dijon mustard, Worcestershire, lemon juice, minced garlic, smoked paprika, kosher salt and black pepper. Mix until combined and silky.

Fold in cheeses and seafood

Fold in 3/4 cup grated Parmesan (reserve 1/4 cup for garnish or extra gratin), shredded mozzarella, chopped artichokes and crab meat gently so the crab stays in lumps. Taste and adjust seasoning with salt, pepper or a squeeze more lemon if desired.

Transfer to baking dish

Spoon the mixture into a shallow 9-inch (or similar) oven-safe gratin dish or cast-iron skillet, smoothing the top so the gratin will brown evenly.

Parmesan Gratin Topping

Combine 1 cup grated Parmesan with panko breadcrumbs (if using) in a small bowl. Stir in melted butter until mixture is evenly moistened. Evenly sprinkle this mixture over the top of the assembled dip. If you prefer a purely cheesy crust, omit panko and use only Parmesan and Pecorino sprinkled on top.

Bake the dip in the preheated oven for 18–22 minutes, until bubbling at the edges and the top is golden brown. For an extra-browned crust, place under the broiler for 1–2 minutes—watch carefully to avoid burning.

Grilled Ciabatta

While the dip is baking, slice the ciabatta on the bias into 12 slices. Brush both sides lightly with extra-virgin olive oil and sprinkle a pinch of sea salt on each slice.

Heat a grill pan or outdoor grill to medium-high. Grill the ciabatta slices 1–1.5 minutes per side until grill marks appear and bread is crisp and warmed through. Immediately rub the hot bread with the cut side of the garlic clove to impart a subtle garlic aroma.

Alternatively, toast the slices under a broiler on high for 1–2 minutes per side, watching closely.

When the dip is done, remove from oven and let rest 3 minutes. Sprinkle chopped fresh parsley over the gratin and serve hot with grilled ciabatta on the side for scooping.