To make these kebabs, start by preparing the marinade. Add all of the marinade ingredients (the onion, water, olive oil, garlic, Worcestershire Sauce, dried rosemary, lemon, kosher salt, and ground black pepper) to a blender and blend until almost smooth. Taste and adjust the sea salt and black pepper as needed, then set it aside.
Next, cut the steak into 1/2 inch cubes and transfer it to a large bowl.
Then, chop the bell pepper and onion and add it to the bowl with the steak.
Pour the marinade into the bowl and toss until the steak, peppers, and onions are fully coated in the marinade.
Then, cover the bowl and transfer it to the fridge to marinate for a minimum of 45 minutes or up to overnight.
When you're ready to grill the kebabs, prepare the wooden skewers by soaking them in a bowl of cold water for a minimum of 30 minutes. This will prevent them from burning!
Once the skewers are ready, prepare the kebabs. Transfer the beef, onion, and bell pepper onto the skewers, layering them one after the other. Repeat until all of the skewers have been assembled.
Next, heat your grill to 500 F.
Once the grill is hot, add the skewers and cook them for 4-5 minutes on each side, until the steak reaches your desired doneness.
Once they're done, remove them from the grill. Serve with a side of labneh, if desired, then serve and enjoy!