Chop all vegetables into small chunks and arrange in greased baking dish. Add chili or pepper, drizzle with olive oil, sprinkle with a little salt and pepper and mix together.
Bake on 425º for about 45 minutes, or until all vegetables are tender and slightly charred.
Heat up tortillas (either using stove, microwave, or oven) and fill with veggie mixture. Top with salsa or chopped avocado and serve!
(To reheat, just put the filled tacos into the oven, covered, until warmed through.)