Heat your oven to 400°F (204°C). Line a baking sheet with parchment paper.
Combine the veggie crumbles with the taco seasoning. If the crumbles are frozen, heat in the microwave for 30 seconds or so and then stir to combine the seasonings. Add more if you prefer more flavor.
Arrange tortilla chips in a single layer on the prepared baking sheet. Top with veggie crumbles mixture, black beans, corn, and shredded vegan cheeses.
Place pan in the oven and bake for 5 to 7 minutes, until the cheese is melted.
As the nachos are baking, chop the cabbage into thin strips, chop the cherry tomatoes into quarters, dice the onion, and thinly slice the jalapeño (being careful not to touch the seeds with bare hands).
In a small bowl, mash the avocado and add the sour cream. Stir together.
When the nachos are done, remove them from the oven and serve them immediately. Top with tomato, red cabbage, onion, jalapeno, and drizzle with creamy avocado mixture.
Optional: Add chopped cilantro.