Wash and dry the romaine lettuce, then chop into bite-sized pieces. Place in a large salad bowl.

Add black beans, corn kernels, diced red bell pepper, halved cherry tomatoes, sliced red onion, and minced jalapeño pepper to the bowl. Toss gently.

In a small bowl, whisk together lime juice, olive oil, ground cumin, chili powder, salt, and black pepper until smooth.

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

Carefully fold in the diced avocado to avoid mashing.

Sprinkle crumbled feta cheese over the top, if desired.

Serve immediately or chill in the refrigerator for up to 30 minutes before serving.