In a medium bowl, gently combine the lump crabmeat, beaten egg, mayonnaise, Dijon mustard, lemon juice, Old Bay seasoning, crushed crackers, and parsley. Season with salt and pepper.

Form the mixture into four patties, about ¾ inch thick. Cover and refrigerate for at least 10 minutes—this helps them hold together.

Heat butter or olive oil in a large skillet over medium heat until shimmering.

Carefully add the crab cakes and cook for about 4–5 minutes per side, or until golden brown and crisp. Avoid overcrowding the pan.

Transfer to a paper towel–lined plate to drain excess oil, then serve immediately.