Rinse the chicken thighs and pat dry with paper towels. Set aside.
Mix the remaining 9 ingredients (lime juice through chili powder) together using a whisk.
Add chicken and stir to coat evenly. Marinate for 2 hours.
Heat grill to medium heat. Brush a small amount of oil on the surface and place chicken thighs on grill.
Add the garlic, cilantro, and jalapeño from the mixture on top of the chicken and grill them until they turn golden brown and charred on both sides.
Serve immediately.