Preheat the oven to 400°F (200°C). Toss the cubed sweet potatoes with olive oil, cumin, smoked paprika, salt, and pepper. Spread them evenly on a baking sheet lined with parchment paper and roast for about 25-30 minutes until tender and slightly caramelized, stirring halfway through.
While the sweet potatoes are roasting, cook the ground beef or plant-based protein in a skillet over medium heat until browned and cooked through, seasoning with salt and pepper. Remove from heat and set aside.
Prepare the chipotle-lime sauce by blending the chipotle peppers, Greek yogurt, lime juice, minced garlic, olive oil, and a pinch of salt in a blender until smooth. Taste and adjust the seasoning if needed.
Arrange the cooked ground meat, roasted sweet potatoes, chopped greens, diced tomatoes, and sliced avocado in serving bowls. Squeeze fresh lime juice over the top for brightness.
Drizzle the smoky chipotle-lime sauce generously over the assembled bowls. Garnish with extra lime wedges, if desired.
Serve immediately and enjoy a vibrant, flavorful taco bowl with contrasting textures of crispy roasted sweet potatoes, tender meat, and fresh toppings.