Prepare all vegetables by finely chopping the red and yellow bell peppers, dicing the red onion, and chopping the tomatoes on a clean cutting board with a sharp chef's knife. Place the chopped vegetables in a large mixing bowl.
Add the drained black beans, thawed corn kernels, and chopped vegetables into the bowl with the prepared ingredients. Toss gently to combine all the components evenly.
In a small bowl or measuring cup, whisk together the olive oil, lime juice, ground cumin, chili powder, and salt and pepper to create a flavorful vinaigrette.
Pour the vinaigrette over the vegetable and bean mixture. Toss thoroughly using a large spoon or salad tongs until everything is coated and well mixed.
Adjust seasoning with additional salt and pepper if needed. Chill in the refrigerator for at least 10 minutes to allow flavors to meld and serve in a serving bowl.