In a large mixing bowl, combine the thawed corn, cherry tomatoes, diced bell pepper, and shredded cheddar cheese.
In a separate bowl, whisk together the sour cream, mayonnaise, lime juice, chili powder, garlic powder, salt, and pepper until smooth.
Pour the dressing over the corn mixture and gently stir until everything is well coated.
Just before serving, fold in the Fritos corn chips to maintain their crunch.
Garnish with chopped fresh cilantro if desired. Serve immediately or refrigerate for up to 1 hour before serving for flavors to meld.