Crab Cakes with Smoky Onion Remoulade

Name: Crab Cakes with Smoky Onion Remoulade
Ingredients: 1 medium onion, halved and thinly sliced; 1 tablespoon canola oil; Kosher salt; 3/4 cup mayonnaise; 1 tablespoon white wine vinegar; 1 1/2 tablespoons minced chives; 1 tablespoon minced shallot; 1/2 teaspoon chili powder; 1/8 teaspoon cayenne; Smoked sea salt, such as Maldon