Preheat oven to 375°F (190°C). Slice sourdough into 3/4-inch thick slices. Brush both sides lightly with olive oil and arrange in a single layer on a baking sheet.

Chop and measure seafood

If not already, pick Dungeness crab meat into bite-sized chunks and roughly chop the bay shrimp. Drain and coarsely chop the artichoke hearts. Finely mince shallot and garlic; chop parsley and slice chives. Measure cheeses and dairy ingredients.

Make the dip

In a medium mixing bowl, beat the softened cream cheese until smooth. Stir in mayonnaise and sour cream until fully combined and creamy.

Mix in grated Parmesan and 1/2 cup of the fontina/Monterey Jack, reserving the remaining 1/2 cup for topping. Add Dijon mustard, Worcestershire sauce, Old Bay, hot sauce (if using), lemon juice, minced shallot, minced garlic, chopped artichokes, chopped parsley, and chives. Season with 3/4 teaspoon kosher salt and 1/2 teaspoon black pepper; taste and adjust seasoning as desired.

Gently fold in the crab meat and chopped shrimp, taking care not to break up the crab too much. Ensure seafood is evenly distributed through the mixture.

Bake & toast

Spoon the dip into a shallow 9-inch ovenproof baking dish (or individual ramekins), smoothing the top. Sprinkle the reserved 1/2 cup fontina/Monterey Jack evenly over the surface.

Place the dip on a middle oven rack and bake at 375°F (190°C) for 18–22 minutes, until the dip is warmed through, bubbly at the edges, and the top is melted and lightly golden. If you prefer a deeper golden crust, broil on high for 1–2 minutes while watching closely.

While the dip bakes, place the prepared sourdough slices in the oven on a separate rack. Toast for 8–10 minutes, flipping once halfway, until crisp and golden. Remove from oven and keep warm.

Finish & serve

Remove the baked dip from the oven and let rest 3–5 minutes. Sprinkle with additional chopped parsley and chives. Serve warm with toasted sourdough slices and lemon wedges on the side for squeezing over the dip or bread.

Storage

Store any cooled leftovers in an airtight container in the refrigerator for up to 2 days. Reheat in a 325°F (160°C) oven until warmed through, about 10–15 minutes.