1. Beat eggs, sherry, onion, salt and pepper in a bowl. Add crab and crackers and lightly stir to mix.
2. Heat butter, in a skillet over medium heat, until hot. Divide crab mixture into 4 mounds and drop into hot butter. Using a spatula, press until flattened into 3 1/2" cakes. Cook about 5 minutes then flip to brown other side for another 5 minutes. Serve with lemon wedges.