Place a rack in the middle of the oven then preheat it to 200 °C / 390 °F. Get a 20 cm x 30 cm (8-inch x 12-inch) baking sheet ready.
Combine shredded chicken, drained sweet corn, drained beans, tomato passata, and roughly chopped onion in a bowl. Season with salt, pepper, oregano, coriander, and olive oil. Stir to combine and optionally add chili if you like spicy.
Arrange the tortilla chips on top of the baking sheet. Sprinkle half of the shredded cheese on top, then spread the chicken topping on top of the cheese. Finish with the rest of the cheese.
bake and serve
Place a baking sheet with the nachos into a preheated oven. Bake for 10 minutes at 200 °C / 390 °F. Optionally serve with sliced avocado, diced onion, and diced coriander.