In a food processor, combine the walnuts, drained chickpeas, taco seasoning and water. Pulse until the beans and walnuts are broken down and the mixture resembles ground beef.
Roughly dice the potato and carrot and add them to a small pot with the cashews. Fill with water and bring to a boil.
Drain and add the mixture to a blender. Add the almond milk, Taco seasoning, and nutritional yeast and blend until smooth.
Cut four of the flour tortillas into quarters. Cut the corners to be rounded.
Working one at a time, place the chickpea beef mixture in the center of each tortilla. Top with the nacho cheese and tostada shell.
Fold the edges up and over the center. Continue to work your way around the tortilla, folding as tight as possible.
Heat the olive oil in a large skillet. Place wrap seam-side down and cook until the underside is golden brown.