Peel and dice the sweet potato into small 1/2-inch cubes to ensure they cook quickly within the 20-minute window.
Heat the olive oil in a large non-stick skillet over medium-high heat and add the sweet potato cubes.
Sauté the potatoes for 8-10 minutes, stirring occasionally, until they are tender and slightly browned on the edges.
Stir in the maple syrup, chili powder, sea salt, and black pepper, coating the potatoes evenly in the sweet and savory glaze.
Add the rinsed black beans and fresh spinach to the skillet, cooking for another 2-3 minutes until the beans are heated through and the spinach is wilted.
Sprinkle the nutritional yeast over the mixture and stir well to create a slightly creamy, savory coating.
Warm the corn tortillas in a separate dry pan or directly over a low gas flame for 30 seconds per side until pliable.
Divide the sweet potato and bean mixture among the tortillas and top each taco with a generous tablespoon of hemp hearts for added protein and crunch.