Grilled Cilantro-Garlic Sirloin and Onions

Ingredients (serves 4)

  • 1 ½ lbs. top sirloin steak
  • 1 bunch of fresh cilantro, stems removed
  • 6 cloves of garlic
  • ¼ cup balsamic vinegar
  • ½ cup + 2 tbsp. olive oil divided
  • 1 tbsp. onion powder or ¼ cup finely minced fresh onion
  • Juice from one large lime
  • 1 jalapeño, seeded and diced (optional)
  • 1 tsp. salt
  • ½ tsp. black pepper
  • 2 large sweet onions
  • 1/3 cup steak sauce


  1. Place the sirloin steak between two pieces of clear plastic wrap and place on the counter.   Using a meat tenderizer or the bottom of a can of vegetables, gently pound on both sides to flatten some and break some of the muscle fibers.
  2. Place the tenderized meat in a large plastic or glass bowl or a large sealable plastic bag.
  3. Place the cilantro, four cloves of garlic, vinegar, lime juice, salt and pepper in a blender or food processor.  Pulse a couple of times and then add ½ cup of the olive oil.  Pulse a couple of more times.
  4. Pour half the marinade into a small container, cover and refrigerate.  Pour the remaining marinade over the steak, toss to coat.  Cover or seal and refrigerate for at least 6 hours or overnight.
  5. Remove marinated steak from the refrigerator and let it come to room temperature for about 20-30 minutes.  
  6. Meanwhile, peel two large sweet onions, keeping them whole.  Once peeled, slice the top off of both onions, and hollow the center (½-¾ inch) stopping just short of going through the bottom.  Place a garlic clove in each hollow.  Place the onions in a microwave safe dish along with 2 tbsp. of water.  Cover and microwave for 4 minutes.
  7. While the onions are cooking, preheat the grill to medium-high heat.
  8. Remove the onions from the microwave and carefully place each onion on a square of aluminum foil (large enough to wrap the onion) with the hollow facing up.  Pour 1 tbsp. of oil in each onion, and then fill each onion with the steak sauce.  Wrap the onions tightly with the foil and then place the packets on the grill, to the side.
  9. Remove the steak from the marinade and gently pat dry.
  10. Place the steak on the hottest part of the grill, cook for 2-3 minutes on each side or until the internal temperature reaches at least 140 degrees F.  Turn the heat down to medium.
  11. Remove the steak from the grill and let it rest for 10 minutes.  Remove the onion packets from the grill.  Cut the steak against the grain and serve it topped with some of the remaining marinade and the grilled onions.
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