Prep the skewers. If using wooden skewers, soak them in water for at least 20 minutes to prevent scorching.

Metal skewers don’t need prep.

Cut evenly. Slice beef, peppers, and onions into uniform 1.25-inch pieces. Even sizing helps everything cook at the same rate.

Make the marinade. In a bowl, whisk olive oil, soy sauce, lemon juice, garlic, brown sugar, smoked paprika, cumin, black pepper, and salt.

Marinate the beef. Toss the beef cubes with the marinade. Rest for 30 minutes on the counter or up to 8 hours in the fridge. Longer marinating equals deeper flavor.

Season the veggies. In a separate bowl, toss peppers, onions, and tomatoes (if using) with a drizzle of olive oil, a pinch of salt, and pepper.

Assemble the kabobs. Thread beef and veggies onto skewers, alternating pieces. Don’t pack them too tight—leave a tiny bit of space for airflow.

Preheat the air fryer. Set it to 400°F (200°C) for 3 to 5 minutes. Preheating helps with quick browning.

Load the basket. Arrange kabobs in a single layer with room between each.

Work in batches if needed.

Cook. Air fry at 400°F for 8 to 12 minutes, flipping halfway. Aim for 130–135°F for medium-rare or 140–145°F for medium using an instant-read thermometer.

Rest and garnish. Let kabobs rest 3 minutes, then sprinkle with parsley or cilantro. Serve with lemon wedges, rice, pita, or a simple salad.