Grilled Steak Fajita Skewers with Avocado Chimichurri

There’s something wonderfully smoky and celebratory about food cooked on skewers. These Grilled Steak Fajita Skewers with Avocado Chimichurri are a weeknight-friendly way to enjoy steak with big, bright flavors—without fuss. Tender sirloin cubes are tossed in a simple spice blend, threaded with colorful bell peppers and red onion, then grilled until lightly charred. A creamy, herb-forward avocado chimichurri finishes everything with a zesty, silky pop that ties it all together.

Why you’ll love this recipe

• Quick to put together: The steak cuts into 1-inch cubes grill fast, perfect for a spontaneous cookout.
• Bright, layered flavors: Warm, smoky spices from the steak meet fresh herbs and lime in the chimichurri.
• Flexible serving options: Serve on skewers, in warm tortillas, over rice, or atop a crisp salad.
• Family-friendly: The mild spice level is crowd-pleasing and easily adjusted to taste.

Ingredients

Make sure you have everything prepped and ready. The ingredient list below is the source of truth for quantities and names.

• ▢2 pounds top sirloin steak cut into 1-inch cubes
• ▢2 tablespoons olive oil
• ▢1 tablespoon chili powder
• ▢¼ teaspoon garlic powder
• ▢¼ teaspoon onion powder
• ▢¼ teaspoon dried oregano
• ▢½ teaspoon paprika
• ▢1 ½ teaspoons ground cumin
• ▢1 teaspoon salt
• ▢1 teaspoon ground black pepper
• ▢1 red bell pepper cut into 1-inch pieces
• ▢1 yellow bell pepper cut into 1-inch pieces
• ▢1 green bell pepper cut into 1-inch pieces
• ▢½ red onion cut into 1-inch pieces
• ▢⅓ cup olive oil
• ▢1 avocado
• ▢3 garlic cloves
• ▢½ cup chopped fresh parsley
• ▢½ cup chopped fresh cilantro
• ▢1 teaspoon salt
• ▢¼ teaspoon ground black pepper
• ▢1 tablespoon fresh lime juice

Equipment

• Grill or grill pan
• Metal or soaked wooden skewers
• Mixing bowls
• Food processor or blender (for chimichurri)
• Tongs

Prep notes

Plan for a short active prep time. Cut your top sirloin into 1-inch cubes so they cook evenly. If you use wooden skewers, soak them in water for at least 30 minutes to prevent burning. Chop the peppers and onion into 1-inch pieces to match the steak cubes for even grilling.

Step-by-step instructions

The directions below are rewritten into clear, sequential steps using the ingredient list as the source of truth. Follow them in order for the best results.

1. Make the steak spice mixture. In a medium bowl, combine 2 tablespoons olive oil, 1 tablespoon chili powder, ¼ teaspoon garlic powder, ¼ teaspoon onion powder, ¼ teaspoon dried oregano, ½ teaspoon paprika, 1 ½ teaspoons ground cumin, 1 teaspoon salt, and 1 teaspoon ground black pepper. Stir until you have a uniform paste-like mixture.
2. Toss the steak cubes with the spice mixture. Add the 2 pounds top sirloin steak cut into 1-inch cubes to the bowl with the spice mixture. Toss thoroughly so each cube is evenly coated. Transfer the seasoned steak to a plate or tray and let it sit at room temperature for 10–15 minutes to take the chill off and allow the flavors to adhere.
3. Prepare the vegetables. While the steak rests, cut 1 red bell pepper, 1 yellow bell pepper, 1 green bell pepper into 1-inch pieces, and slice ½ red onion into 1-inch pieces. Keep everything in a single layer on a cutting board or in a shallow dish for easy assembly.
4. Assemble the skewers. Thread the seasoned steak, red pepper pieces, yellow pepper pieces, green pepper pieces, and red onion pieces onto skewers, alternating steak and vegetables for even distribution. Aim for 3–4 steak cubes per skewer depending on your skewer length, leaving a little space at each end for handling. If using wooden skewers, ensure they were soaked previously.
5. Preheat the grill. Heat your grill or grill pan to medium-high. If using a charcoal grill, allow coals to become evenly hot and covered with gray ash. For gas grills, preheat with the lid closed until you reach a steady medium-high temperature. Lightly oil the grates or brush the grill pan with a little oil to prevent sticking.
6. Grill the skewers. Place the assembled skewers on the hot grill. Cook for about 3–4 minutes per side, rotating to get even sear marks and a nice char on the bell peppers and steak. Total cook time should be roughly 8–12 minutes depending on your grill and how well-done you like your steak. Remove skewers when steak reaches your preferred doneness—use an instant-read thermometer if you prefer: 125–130°F for medium-rare, 135°F for medium.
7. Rest the skewers. Transfer the cooked skewers to a clean plate and loosely tent with foil. Rest for 5 minutes so the juices redistribute and the steak stays tender.
8. Make the avocado chimichurri. While the skewers rest, prepare the chimichurri: In a food processor or blender, combine ⅓ cup olive oil, 1 avocado (scooped from its skin), 3 garlic cloves, ½ cup chopped fresh parsley, ½ cup chopped fresh cilantro, 1 teaspoon salt, ¼ teaspoon ground black pepper, and 1 tablespoon fresh lime juice. Pulse until the mixture is mostly smooth but still slightly textured. Taste and adjust salt or lime if needed.
9. Serve. Drizzle the avocado chimichurri over the warm skewers or serve it on the side for dipping. Pair with warm tortillas, rice, or a crisp salad, and garnish with extra chopped herbs or lime wedges if desired.

Troubleshooting & tips

• If your steak is cooking unevenly, make sure pieces are similar in size — 1-inch cubes give the most predictable results.
• For char without overcooking, sear over direct heat and move to a cooler section of the grill if the peppers or steak are browning too fast.
• Don’t over-blend the chimichurri. You want some herb texture to keep it bright and fresh.
• If you’d like more heat, add a pinch of red pepper flakes to the steak seasoning or a sliced jalapeño to the chimichurri.

Serving suggestions

These skewers are versatile. Here are a few ways to enjoy them:

• Serve right off the skewers with warm flour or corn tortillas and extra chimichurri for DIY steak fajitas.
• Plate over cilantro-lime rice or a simple quinoa pilaf for a heartier meal.
• Lay the sliced steak and vegetables atop a bed of mixed greens and drizzle with chimichurri for a vibrant salad.

Make-ahead and storage

Prepare the chimichurri up to 24 hours ahead and keep it in an airtight container in the refrigerator; bring to room temperature before serving. Steak skewers are best eaten the day they’re made, but cooked components will keep in the fridge for up to 3 days. Reheat gently in a 300°F oven or on a low grill, covered, to prevent drying out.

Flavor variations

• Swap the top sirloin for a different cut if desired; just keep the cubes near 1 inch for consistent cooking.
• Try smoked paprika instead of regular paprika for an extra smoky layer.
• Use Greek yogurt or a splash of vinegar in the chimichurri for tangy complexity.

Final thoughts

These Grilled Steak Fajita Skewers with Avocado Chimichurri are everything you want for a casual gathering: colorful, quick, and full of balanced flavors. The spice-coated sirloin develops a gorgeous char on the grill while the avocado chimichurri adds a silky, herbaceous finish that keeps each bite bright. Whether you’re feeding a crowd or making a simple weeknight meal, these skewers deliver a satisfying mix of textures and flavors with minimal fuss.

Enjoy and happy grilling!