In a large, heavy-bottomed pan, heat the vegetable oil over medium heat until a deep-frying thermometer inserted in the oil reaches 350 degrees F.
Prepare a baking tray lined with paper towels.
Combine the flour, cornmeal, black pepper, paprika, and garlic powder, in a shallow bowl.
Put the egg whites, and a pinch of salt into another bowl, and whisk until the mixture is frothy. Dip the okra in the egg whites and allow the excess egg whites to drip off, then dip the okra into the flour mixture, shake off the excess flour, and gently drop into the preheated oil.
Fry the vegetables until golden brown, turning frequently for even color.
Transfer the fried okra to a tray, lined with paper towels to absorb the excess oil, and season with salt, to taste. Coat, and fry, and season the remaining okra. Serve with the Chipotle Sour Cream.
Combine the sour cream, lime juice, chopped chipotle pepper, and salt, and pepper, to taste, in a bowl. Mix to incorporate well. Serve the dipping sauce alongside the Crispy Cornmeal Okra.