In a medium bowl, whisk together chili powder, cumin, paprika, lime juice, and a pinch of salt until well combined. Add the chicken thighs, ensuring they are fully coated in the marinade. Cover the bowl with plastic wrap and let the chicken marinate for at least 15 minutes at room temperature or refrigerate for up to overnight for deeper flavors.

Heat a large skillet over medium heat and add a splash of oil if needed. Once hot, add the marinated chicken thighs to the pan. Cook for 7-10 minutes on each side, or until the chicken is golden brown and registers an internal temperature of 165°F. Remove the chicken from the skillet and let it rest for a few minutes before slicing.

While the chicken is resting, prepare the pineapple salsa by chopping the fresh pineapple into small cubes and finely dicing the red onion. In a bowl, combine the pineapple, red onion, chopped cilantro, and squeeze in some lime juice. Mix everything thoroughly for a refreshing salsa that will complement the Pineapple Chicken Tacos beautifully.

Warm the tortillas in the skillet for a few seconds on each side until pliable. Once heated, slice the rested chicken into strips and place them on each tortilla. Generously top with the fresh pineapple salsa and feel free to add sliced jalapeños or creamy avocado for an extra layer of flavor. Enjoy your vibrant Pineapple Chicken Tacos!