In a skillet heat up the oil on low-medium heat, and then add onion, jalapeno, and garlic (and other peppers if you're using them). Cook for roughly 5 minutes, until onions soften.
Add mushrooms, taco seasoning, and 1/4 cup of water to skillet. Stir and cook for another 5 minutes.
Remove from heat and set aside
Place a tortilla on a large plate. We put our toppings on one half of the tortilla so it can be folded easily
Add a couple spoonfuls of your cooked mushroom mixture, black beans, and drizzle some cashew queso.
Grab a tostada and break it in half and add it on top of the queso.
Add fresh ingredients on top of the tostada pieces; shredded lettuce, tomato, scallions, cilantro, and basil.
Finish teh top with avocado if you’re using it.
In a large skillet add some oil and turn to low heat. Once oil is heated, fold over the tortilla and transfer it to the skillet. Cook for 2-3 minutes per side.