Slice the onion, smash the garlic, cut the jalapeños in half, slice the lime, and toss all the ingredients into the cast iron.
Place the herbs on top.
Spatchcock your chicken: Cut down both sides of the backbone with a sharp knife or kitchen shears. Flip the chicken over and press down on the middle of the breasts to break the bone. Transfer to the cast iron.
Once everything is in one pan, lightly drizzle olive oil over the chicken and season. Then pour the beer around it.
Cover the chicken with foil and transfer to the grill.
Keep the chicken covered until it hits an internal temp of about 120°F, then remove the foil and continue to cook until the internal temperature reaches 165°F.
Let rest for about 5 minutes and serve!
Notes
If you're not sure about how to spatchcock a chicken, we have included detailed instructions and photos above.