In a medium mixing bowl, combine the tomatoes, bell pepper, cilantro, and 1/2 teaspoon salt. Set aside.
In a small mixing bowl stir together the sour cream, mayonnaise, scallions, lime juice, remaining 1/2 teaspoon salt, and chili powder. Set aside.
Into a serving bowl, sprinkle half of the cornbread in an even layer.
Continue layering with half each of the black-eyed peas, corn, tomato mixture, sour cream mixture, and cheese.
Repeat the layers with the remaining ingredients, ending with cheese.
Cover and refrigerate at least 2 hours and up to overnight. Serve chilled.