For the cheese - chop sweet potato into large, even chunks. Place sweet potato chunks into a pot, cover with water, cover the pot with a lid, and bring to a boil. Once you can easily pierce the potato with a fork (after about 5-10 minutes of boiling) they are done. Strain the water and set aside to cool. Once cool remove the skin (the skin will easily peel off). In a high speed blender, add the cashew and water. Blend on high for a minute or until it reaches a smooth creamy consistency. Next add the sweet potato to the blender along with the nutritional yeast, salt, and pepper. Blend on high until super smooth. You may need to work the blender a bit with a plunger (if using Vitamix) or stop the blending once or twice to scrape the sides of the blender down to make sure it reaches the right consistency. Now the ooey, gooey cheese is done. YUM!
For the beans - heat a medium or large frying pan. Add 1 teaspoon oil to the pan followed by the onion. Once the onion is translucent, add the garlic. Next, add the smoked paprika, cumin, salt and pepper. Next add the butter and black beans. As soon as all of the ingredients are evenly mixed you can turn off the heat, the beans are done.
To assemble a quesadilla - spray a little oil down on a medium-hot pan or smear one side of the tortilla with butter. Put the tortilla (butter side down) on the hot pan, put a few scoops of the cheese on one side of the tortilla as well as the bean and onion combo. Fold the quesadilla over. Cook for about 3 minutes on each side or until tortillas reaches your desired crispness.