Gather all ingredients including fresh corn, tomatoes, red onion, avocado, cilantro, lime, chili powder, and olive oil.

If using fresh corn, boil in a large pot of water for 5-7 minutes until tender. If using frozen corn, sauté in a skillet for 5-8 minutes until golden brown.

Let the corn cool slightly, then chop the tomatoes and red onion into small pieces.

Soak diced onions in cold water for 10 minutes to mellow their sharpness.

In a large bowl, combine the corn, tomatoes, onion, avocado, cilantro, lime juice, feta cheese, chili powder, olive oil, salt, and pepper.

Toss gently to combine all ingredients and serve immediately or chill before serving.