Step 1In a small bowl, combine the paprika, oregano, salt, garlic powder, onion powder, cayenne pepper, black pepper and sugar. This makes about 1 tablespoon spice mix, more than is needed for the remainder of the recipe; the mix will keep, sealed in an airtight container at cool room temperature, for weeks.
Step 1In a small saucepan, melt the butter over medium heat. Add the shallot and cook, stirring often, until softened, about 5 minutes. Add the flour and cook, whisking often, until golden and just beginning to smell nutty, about 3 minutes. Whisk in the wine, bring to a boil and when just thick, 30 seconds to 1 minute, whisk in the broth. Bring to a boil and cook until thick enough to coat a spoon, 3 to 4 minutes. Add the cream, bring to a simmer and cook, whisking occasionally, until the mixture is again thick enough to coat a spoon, 3 to 4 minutes. Remove from heat, whisk in mustard, season with salt to taste, cover and keep warm. This makes about 1 1/2 cups of sauce.
Step 1In a small bowl, beat the egg just to blend. Remove 2 tablespoons of the egg. Reserve the remaining egg for another use.
Step 2In another bowl, mix together the 2 tablespoons of beaten egg, mayonnaise, parsley, blackening spice and a pinch of salt. Fold in the crabmeat just until coated, taking care not to break it up too much. Divide the crab mixture into 4 equal portions.
Step 3Place a 3-inch ring mold or biscuit cutter on a parchment-lined baking sheet and pack one portion of the crab mixture tightly into the mold. Smooth the top and carefully remove the ring mold. Repeat with the remaining 3 portions. Cover with plastic wrap and chill until firm, at least 1 hour and preferably overnight.
Step 4Heat the oven to 400 degrees. In a large, ovenproof, nonstick skillet heat 1 tablespoon of oil and 1 tablespoon of butter over medium heat. Working with 2 crab cakes, sprinkle 1 teaspoon of breadcrumbs over each and carefully place, crumb side down, in the skillet. Cook, occasionally swirling the fat in the pan, until the bottom sides of the crab cakes are deep, golden brown, 5 to 7 minutes. Sprinkle 1 teaspoon of breadcrumbs over the top sides of each crab cake, then very carefully turn over (you may need to use 2 spatulas as cakes will be very delicate). Cook until breadcrumbs are golden, 2 to 3 minutes. Transfer to a plate. Use paper towels to wipe out the skillet and repeat with remaining oil, butter, crab cakes and breadcrumbs.
Step 5When the second batch of crab cakes is done, wipe the skillet clean, return the crab cakes from the plate to the skillet and transfer to oven and heat until cooked through, 5 to 7 minutes.
Step 6Serve crab cakes over mustard sauce topped with parsley.