In a medium bowl, whisk together the fresh orange juice, lime juice, minced garlic, ground cumin, dried oregano, smoked paprika, and a generous pinch of salt and pepper. Ensure all ingredients are well blended to create a tasty marinade.
Place the boneless chicken thighs into a resealable plastic bag or a shallow, non-reactive dish. Pour the marinade over the chicken, ensuring each piece is thoroughly coated. Seal the bag or cover the dish with plastic wrap. Refrigerate and allow to marinate for at least 1 hour, or for better flavor, overnight.
When you're ready to cook, preheat your grill or a skillet over medium-high heat. Add the olive oil to the skillet once it’s hot, allowing it to coat the bottom evenly.
Remove the chicken from the marinade, letting any excess liquid drip off. Place the chicken on the grill or in the skillet, cooking for about 6-7 minutes on each side, or until fully cooked through. The internal temperature should reach 165°F (74°C) to ensure it’s safe to eat.
After the chicken has finished cooking, take it off the heat and let it rest for a few minutes. This allows the juices to redistribute; then slice the chicken into attractive strips.
While the chicken is resting, take the corn tortillas and warm them on the grill or in a separate skillet until they become soft and pliable—about 30 seconds on each side should suffice.
To assemble your delicious tacos, lay an enticing few slices of chicken on each tortilla, then generously top with shredded red cabbage and creamy avocado slices.
For a beautiful and appetizing finish, garnish each taco with fresh cilantro leaves. Serve immediately with lime wedges on the side, perfect for squeezing over the top for that zesty burst of flavor.