In a medium bowl, combine the diced chicken, garlic, cumin, smoked paprika, lime juice, and a pinch of salt and pepper. Toss to coat the chicken evenly and let it marinate for about 15 minutes.
Heat the olive oil in a large skillet over medium-high heat. Add the marinated chicken to the skillet and cook for about 6-8 minutes, or until fully cooked and slightly crispy, stirring occasionally.
Once the chicken is cooked, add the diced mango, red onion, red bell pepper, and jalapeño to the skillet. Stir everything together and cook for an additional 3-4 minutes until the vegetables are slightly softened.
Warm the corn tortillas in a separate skillet or directly over a low flame until pliable.
Assemble the tacos by placing a generous portion of the spicy mango chicken mixture onto each tortilla.
Top each taco with fresh avocado slices and a sprinkle of chopped cilantro for garnish.