Build the Campfire: Start a stable campfire and allow it to burn down to medium-hot embers. Arrange coals for direct and indirect heat zones. Alternatively, preheat a camping stove over medium heat.
Roast the Sweet Potatoes: Toss diced sweet potatoes in olive oil, cumin, smoked paprika, and a pinch of salt. Spread them on the campfire grill or wrap them in foil. Roast over medium heat for 15-20 minutes, flipping occasionally for even cooking.
Cook the Black Beans: Heat a cast-iron skillet on the grill or stove. Add a splash of olive oil, followed by black beans and lime juice. Cook for 5-7 minutes, stirring occasionally.
Warm the Tortillas: Lay tortillas directly on the grill for 30 seconds per side, or until slightly charred and pliable. Stack and cover with a clean towel to keep warm.
Assemble the Tacos: Start with a warm tortilla as the base. Add roasted sweet potatoes, black beans, and your favorite toppings like avocado, salsa, and cilantro. Add optional toppings for extra flavor, such as queso fresco or hot sauce.