In a large mixing bowl, combine the black beans, corn, diced bell pepper, jalapeño slices, olive oil, ground cumin, chili powder, salt, and pepper. Mix well until everything is evenly coated.
On a large baking sheet, spread the tortilla chips in an even layer.
Sprinkle half of the shredded cheddar cheese over the chips evenly.
Top the chips with the veggie mixture, spreading it out evenly over the nachos.
Sprinkle the remaining cheddar cheese on top of the veggie layer.
Bake in the preheated oven for about 10-12 minutes, or until the cheese is melted and bubbly.
Remove the nachos from the oven and let them cool slightly.
Just before serving, add the diced avocado on top and dollop sour cream or Greek yogurt over the nachos.
Finish with a generous sprinkle of chopped cilantro.
Notes
Feel free to customize the toppings based on your preferences.