In a large bowl, combine the chicken thighs, olive oil, salt, black pepper, cumin, chili powder, smoked paprika, and minced garlic. Mix well to coat the chicken evenly with the spices.
In a large skillet over medium heat, add the seasoned chicken and diced onion. Cook for about 5 minutes, stirring occasionally, until the chicken is browned on all sides.
Pour in the chicken broth and lime juice, then bring the mixture to a simmer. Cover the skillet and reduce the heat to low. Cook for 30-35 minutes, or until the chicken is tender and easily shredded with a fork.
Once cooked, remove the chicken from the skillet and shred it using two forks. Return the shredded chicken to the skillet and cook uncovered for an additional 5-10 minutes to allow the liquid to evaporate and the chicken to crisp up slightly.
While the chicken is crisping, warm the corn tortillas in a separate skillet over medium heat for about 30 seconds on each side.
Assemble the tacos by placing a generous portion of the crispy chicken on each tortilla. Top with diced avocado, chopped cilantro, and diced red onion. Serve with lime wedges on the side.