Step 1: In a medium bowl, gently whisk together the large egg, mayonnaise, Dijon mustard, Worcestershire sauce, and Old Bay seasoning until well combined.
Step 2: Stir in the chopped fresh parsley.
Step 3: Add the lump crab meat and breadcrumbs to the wet mixture. Using a rubber spatula, carefully fold the ingredients together. The goal is just to combine them without breaking up the crab lumps. Don't overmix!
Step 4: Divide the mixture into 6 equal portions and gently shape them into patties, about 1-inch thick. Avoid pressing too firmly.
Step 5: Place the formed crab cakes on a plate, cover loosely, and refrigerate for at least 30 minutes. This chilling step is vital as it helps the cakes firm up and prevents them from falling apart during cooking.
Step 6: Heat the butter in a large non-stick skillet over medium heat until melted and lightly bubbling.
Step 7: Carefully place the chilled crab cakes into the hot skillet. Cook for 3-4 minutes per side, or until they are beautifully golden brown and crispy. Cook in batches if necessary to avoid overcrowding the pan.