Preheat your oven to 400.
In a bowl, toss the diced sweet potato with the oil, 1 tsp chili powder, 1 tsp cumin, a pinch of coarse salt and pepper. Roast for 30 minutes on a foil-lined baking sheet.
In a small sauce pan add the beans and season with the remaining cumin, chili powder and garlic salt. Heat for about 5 minutes over medium heat.
Warm tortillas and spoon on some beans, followed by sweet potatoes. Top with diced avocado, queso fresco, a little lime juice, and cilantro leaves.