Preheat your grill to medium-high heat. If you're using a gas grill, set it to about 400-450°F. If you're using a wood fire grill, let the coals burn down until they're glowing red with a thin layer of white ash.

While the grill is heating up, prepare your vegetables and set them aside. Mix together the olive oil, lemon juice, and vinegar in a small bowl.

Season your beef with salt, black pepper, and the red pepper flakes. Place it in a resealable plastic bag or on a cutting board and brush it with the olive oil mixture.

Place the grill grates over the heat and brush them with oil to prevent sticking. Place the beef and vegetables on the grates and cook for about 6-8 minutes on each side for medium-rare, or longer if you prefer your beef more well-done.

While the beef is cooking, make your chimichurri sauce by mixing together a cup of chopped fresh parsley, a minced garlic clove, a tablespoon of red wine vinegar, a teaspoon of dried oregano, a pinch of red pepper flakes, and salt and black pepper to taste. If you have a food processor, pulse everything together until well combined. If not, mix everything together in a small bowl.

Once the beef has reached your desired level of doneness (use a meat thermometer to check for an internal temperature of 145°F for medium-rare), remove it from the grill and let it rest for about 10 minutes.

While the beef is resting, grill your blood sausage or chorizo, if using. Simply place them on the grates and cook for about 5-6 minutes on each side, or until they're heated through.

Once everything is cooked to perfection, it's time to serve! Slice the beef against the grain and arrange it on a platter with the grilled vegetables and sausage. Serve with the chimichurri sauce on the side.