In a small mixing bowl, whisk together sour cream and olive oil until smooth. Add salt, black pepper, garlic powder, onion powder, and ground cumin. Whisk for 1-2 minutes and set aside.

In a large mixing bowl, combine sweet corn, black beans, Rotel tomatoes, and diced bell pepper. Fold in shredded cheddar cheese. Mix gently.

Pour the dressing over salad mixture and gently stir to coat everything evenly with the dressing.

Just before serving, fold in Fritos to maintain their crunch.

Garnish with extra Fritos, shredded cheddar, or chopped cilantro. Serve chilled or at room temperature.