Heat olive oil over medium heat in a 14 inch skillet if 12 inch is your largest, you may have to increase cooking times by a few minutes. Add onion and cook for three minutes. Add mushrooms and grated sweet potato, season with salt, cumin, and cayenne. Cook, breaking large mushroom slices in half and stirring often until soft, about eight minutes. Stir in black beans and kale. Cover with a baking pan or a lid and cook about three or four more minutes, until heated through. Transfer to a serving bowl.

Wrap tortillas in a damp towel and microwave in 30 second intervals until warm. Serve wrapped in the damp towel so they stay warm and moist.

Put cabbage, avocado slices, yogurt, lime wedges, and cilantro out on the table and allow everyone to assemble their soft tacos with their desired toppings a squeeze of lime juice is a must..