Preheat oven to 425 degrees F. Spray a baking dish with nonstick spray. In a small bowl, combine salt, pepper, paprika, chili powder, cumin and garlic powder, mixing to combine.
Pat chicken thighs dry with a paper towel, then cover in the spice rub. Place the sliced onion all over the bottom of the baking dish and set the chicken over top. Place lime wedges in between the chicken. Cover with foil and bake for 45-60 minutes. Remove chicken and let cool slightly, then shred.
A few minutes before the chicken is shredded, make the goat cheese queso below. To assemble tacos, warm the tortillas then cover in chicken, queso, tomatoes, onions, avocado and extra crumbled goat cheese