Heat the olive oil in a medium skillet over medium heat. Saute the onions until translucent and tender, 3 to 4 minutes. Add the seafood seasoning and garlic and saute 1 minute longer. Let cool completely.
In a large bowl, combine the crab meat, mayonnaise, parsley, mustard, salt, pepper, bread, egg, lemon zest and sauteed onions. Scoop the crab mixture using a 1/3-cup measure and form cakes (they may be slightly loose; see Cook's Note). Transfer to a baking sheet and refrigerate for 30 minutes.
In a large skillet, heat 1 tablespoon olive oil over medium-high heat. Cook the crab cakes in batches, adding more oil if needed, until golden brown, about 3 minutes per side. Serve atop salad greens with a drizzle of Remoulade Sauce.
Whisk together the mayonnaise, ketchup, capers, relish, mustard and lemon juice in a medium bowl until well combined. Season with salt and pepper.
These crab cakes are loose to maintain the crab flavor. They will not be as tightly packed as other crab cakes and may fall apart a bit, but they taste awesome! You can also use a ring mold to pack them more tightly.