Rub the ribs with canola oil, then season thoroughly. If you’re using the simple mix, go heavy enough to create a real crust. That salty bark is part of what makes churrasco feel like churrasco.
Set up your grill for medium-low heat, aiming for 275–300°F, and keep the heat source about 6–8 inches away from the meat. If you have a grilling basket or cage, secure the ribs in it. If you don’t, no problem. The key is indirect roasting close enough to the coals to build color without burning.
Start with the ribs bone side away from the fire for about 30 minutes. Rotate if needed so each rack gets a chance to form that initial crust. Then flip so the bone side faces the fire and keep cooking for about 3.5–4 hours, until the ribs are tender and the meat has pulled away from the bones.
Every 30 minutes, baste lightly with beer or beef broth. This step helps prevent the surface from drying out, especially if your fire runs slightly hot. You’re not trying to “wash” the rub off, just keep the edges from turning dry.
When the ribs reach 180–200°F internally, they should feel tender when probed. Pull them off and rest for 20 minutes. Slice between the bones, spoon the red onion and herb sauce over the top, and serve immediately.
This is one of those dishes where the contrast is the whole point: rich vs bright, smoky vs fresh, salty crust vs soft interior.