The cooked potatoes are peeled with a paring knife and chopped, yielding about 1 cup.
In a medium pot, we start to heat the oil over low heat. The onion is peeled and chopped, yielding ½ cup. It is added to the pot and the heat raised to medium. After a few minutes, we stir and add the green pepper.
We smash the clove of garlic (carefully!) with the side of our chef knife, discarding the peel. We sprinkle the salt on to the garlic and mince. When the onion and pepper are tender, we stir in the garlic. After another minute, we add the cumin and chile powders and stir well. The heat is lowered to medium-low.
The chopped sweet potatoes are added, smooshing them down with a spoon and stirring them in to combine them with the vegetables and spices.
Next, we stir in the black beans. Using the microplane, the zest of the orange is added. With kitchen scissors, we cut and add the sage leaves directly to the pot. We also stir in the Chipotle hot sauce.
The mixture is cooked a few more minutes to meld the flavors.
The tortillas are wrapped in a damp paper towel and heated in the microwave for 30 seconds. Meanwhile, we add the juice of the orange to the black bean and sweet potato mixture.
We fill each tortilla, adding cilantro and additional hot sauce as desired.