In a large bowl, toss the diced sweet potatoes with olive oil, chipotle powder, smoked paprika, cumin, salt, and pepper until evenly coated.
Spread the seasoned sweet potatoes on a baking sheet lined with parchment paper in a single layer.
Roast in the preheated oven for 25-30 minutes, or until tender and slightly caramelized, flipping halfway through.
While the sweet potatoes are roasting, warm the tortillas in a skillet over medium heat for about 30 seconds on each side, until pliable.
In a separate bowl, mix the black beans with a pinch of salt and a squeeze of lime juice for extra flavor.
Once the sweet potatoes are done, assemble the tacos by placing a generous scoop of sweet potatoes on each tortilla, adding a spoonful of black beans, slices of avocado, and a handful of red cabbage.
Garnish with fresh cilantro, a drizzle of Greek yogurt or sour cream if desired, and a squeeze of lime juice for an extra zesty kick.
Notes
Optional toppings include Greek yogurt or sour cream.