Preheat oven to 425℉. Line a rimmed baking tray with aluminum foil for easy clean up. Use a baking dish that can go under the broiler (not glass).
Trim off any excess fat from the thighs (a little is okay because it will cook off in the oven).
Mix the olive oil, lime zest, lime juice, chili powder, cumin, garlic powder, onion powder, salt, pepper and brown sugar in a small bowl. Mix to form a paste.
Brush the seasoning mixture all over the thighs, evenly coating the top and bottom. Spread the chicken thighs on the lined baking dish in an even layer.
Bake the chicken for 18 minutes, then turn the broiler on high and cook for an additional 4-6 minutes to caramelize the tops. The chicken is done when the internal temperature reaches 165℉ when checked with a meat thermometer or when the juices run clear.
Remove the chicken from the oven and loosely tent with foil. Let rest for 5 minutes before serving. Enjoy with rice, pasta, salads, or piled into sandwiches.
