Preheat your oven to 375°F (190°C).
In a small bowl, mix together the chili powder, cumin, garlic powder, onion powder, paprika, salt, and pepper.
Rub the chicken breasts with olive oil, then season them generously with the spice mixture, coating both sides.
Place the seasoned chicken breasts on a baking sheet lined with parchment paper or aluminum foil.
Bake in the preheated oven for 20-25 minutes, or until the chicken is cooked through and no longer pink in the center. Internal temperature should reach 165°F.
Once cooked, remove the chicken from the oven and let it cool slightly. Use two forks to shred the chicken into bite-sized pieces.
Turn up the oven temperature to 400°F (200°C).
Place the tortillas on a baking sheet, arranging them so they are slightly overlapping. Divide the shredded chicken evenly among the tortillas, placing it on one half of each tortilla. Sprinkle shredded cheese over the chicken for each tortilla.
Carefully fold the side of each tortilla over the filling to create a taco shape, securing them with toothpicks if needed. Spray the tops with a cooking spray evenly, so the tortillas get crispy.
Bake the assembled tacos in the preheated oven for 10-12 minutes. Broil for 2-3 minutes at the end, so you get an even crispier tortilla. Watch them very carefully so they do not burn.
While the tacos are baking, make the Avocado Lime Crema. In a blender or food processor, combine the avocado, sour cream, lime juice, cilantro, salt, and pepper.
Remove the tacos from the oven and let them cool slightly before serving. Drizzle each taco with the avocado lime crema and top with your desired toppings, such as cilantro, pickled red onions and lime wedges.