Grilled Beef Barbacoa Tacos

Ingredients:

• 2 small red onions
• 1 plum tomato, halved lengthwise
• 1/4 cup vegetable oil + extra for drizzling
• 1/3 cup cilantro, coarsely chopped
• 2 tsp smoked paprika
• 2 tsp. brown sugar
• 3/4 tsp ground cumin
• 0.5 tsp dried oregano
• 2 cloves garlic, chopped
• 2 medium chipotle peppers in adobo sauce
• 3/4 cup + 1 tbsp apple cider vinegar
• 1.3 kg beef shoulder, cut into 5 cm pieces.
• Warmed corn tortillas on the grill, for serving
• To serve: avocado slices, cilantro leaves, sour cream

Preparation:

1. Preheat grill, preparing indirect and direct heat zones.
2. For gas grills with 3 or more burners: Turn all burners to medium-high heat; after about 15 minutes, turn off one of the middle burners and reduce the heat of the others to medium.
3. For charcoal grills: Place one chimney full of burnt-out coals on one side of the grill. Place a grease tray on the other side to prevent flare-ups.
4. Halve and peel the onion. Cut one half into two wedges. Slice the remaining onion half into 0.3 cm thick half-moons and set aside for marinating. Drizzle the tomato halves and onion wedges with vegetable oil and season with salt and pepper. Grill the tomatoes and onion wedges on the hot side of the grill, covered, until dark grill marks appear, about 5 minutes per side.
5. Place the roasted tomatoes and onions in a food processor along with 1/4 cup vegetable oil, chopped cilantro, smoked paprika, brown sugar, cumin, oregano, garlic, chipotle pepper, 1 tablespoon vinegar, 2 teaspoons salt, and 1/2 teaspoon black pepper. Process until smooth. Transfer to a large bowl and add the beef pieces. Season with pepper.
6. Place a large, double-layer sheet of wide, heavy-duty foil on the countertop. Place the beef in the center. If using regular foil, divide the beef into 2 foil parcels. Bring the short sides of the foil together and fold them twice to seal, then fold the other sides over to form a parcel, leaving a space for steam. Place over indirect heat on the grill and cover. Cook until the meat is tender and flakes easily, 2.5 to 3 hours.
7. Meanwhile, in a small saucepan, combine 3/4 cup vinegar, 3/4 cup water, and 1.5 teaspoons salt and heat over medium-high heat. When the mixture comes to a boil, stir in the reserved chopped onion and turn off the heat. Cool the mixture completely and refrigerate until ready to serve.
8. Shred the beef with forks and return it to the sauce; stir well to coat. Serve with warm tortillas, pickled red onions, and other toppings of your choice.