In a large bowl, whisk together mayonnaise, beaten egg, Dijon mustard, Worcestershire sauce, Old Bay seasoning, lemon juice, and black pepper until smooth.

Fold in panko breadcrumbs until evenly moistened. Add diced red bell pepper, onion, and parsley, mixing to combine.

Gently fold in lump crab meat with a rubber spatula using broad, careful strokes. Stop as soon as crab is just coated, being careful not to break up lumps.

Line a baking sheet with parchment paper. Scoop about 1/2 cup mixture per cake and gently form into 8 patties, each about 3 inches across and 1 inch thick.

Cover patties with plastic wrap and refrigerate for at least 30 minutes or up to 4 hours to firm up.

Heat olive oil and butter in a large non-stick or cast-iron skillet over medium-high heat until butter foams and oil shimmers.

Carefully place chilled crab cakes in the hot pan, leaving space between them. Cook in batches if needed to avoid crowding.

Fry for 4-5 minutes per side until deep golden brown and crispy. Flip only once using a thin fish spatula.

Transfer to a wire rack to drain briefly. Serve immediately with tartar sauce, remoulade, or lemon wedges.