Thaw frozen corn and drain, or boil fresh corn for 3-5 mins until tender.

Chop the vegetables: halve tomatoes, dice cucumbers, and finely chop onion.

Combine the chopped vegetables and cooled corn in a mixing bowl.

In a separate bowl, whisk together mayonnaise, sour cream, lime juice, garlic powder, chili powder, salt, and pepper.

Pour the dressing over the salad and toss gently to coat.

Cover and refrigerate for at least 30 minutes before serving.