In a bowl, whisk together the olive oil, red wine vinegar, minced garlic, dried oregano, smoked paprika, salt, and black pepper.
Place the flank steak in a shallow dish or resealable plastic bag and pour the marinade over the steak, making sure it is evenly coated. Cover the dish or seal the bag and refrigerate for at least 30 minutes or up to 2 hours.
Preheat the grill or grill pan over medium-high heat. Remove the steak from the marinade and discard any excess marinade.
Grill the steak for 5-7 minutes on each side, or until it reaches your desired level of doneness. Use tongs to flip the steak and avoid puncturing it, which will cause juices to escape.
Remove the steak from the grill and let it rest for 5 minutes.
Slice the steak thinly against the grain and serve immediately.
Churrasco is traditionally served with chimichurri sauce and a side of salad or grilled vegetables.
Notes
Storage:Churrasco can be stored in an airtight container in the refrigerator for up to 3 days. To reheat, heat on a grill or in a skillet until warmed through. Avoid overcooking the steak, as it will become tough and dry.