Лук в кляре

For the Outback sauce: 1/2 cup mayonnaise 1 tablespoon ketchup 2 tablespoons horseradish sauce 1/2 teaspoon paprika 1/4 teaspoon salt 1/8 teaspoon dried oregano 1 pinch ground black pepper 1/4 teaspoon cayenne pepper For the onion: 1 large sweet onion 1 cup all-purpose flour 1/4 teaspoon cayenne pepper 1 teaspoon paprika 1/8 teaspoon dried thyme 1/8 teaspoon dried oregano 1/4 teaspoon ground cumin 1 teapoon salt Freshly ground black pepper 1 large egg 1 cup whole milk 1 gallon vegetable oil