Preheat the oven to 400 °F (204°C).

Place the onion and garlic in a food processor and pulse until fully chopped/pureed. Place it in a large bowl.

Into that same bowl, add in the beef, tomato paste, Greek yogurt, ground cumin, paprika, red pepper flakes, salt, and pepper.

Using clean hands, mix well until thoroughly combined.

Grab a large sheet of parchment paper and place one of the pieces in the middle. Place another sheet of parchment on top and, using a rolling pin (or your hands), roll it out into a rectangle. Do your best to make it as even as possible.

Remove the parchment paper on top. Starting from the bottom with the short side facing you, roll the meat (with the parchment paper) onto itself in 2-inch increments until complete. Transfer it to a large sheet pan.

Repeat the same process for the remaining pieces.

Move the rolled meat to the side and add the tomatoes and peppers to the same sheet pan. Drizzle them with olive oil and season with salt and pepper.

Transfer it to the oven and bake for 20 minutes.

When done, unfold the rolled meat and tear it into large pieces.

To make the sauce, melt the butter in a small saucepan over medium heat. Add the tomato paste and water and mix until combined. Cook until it comes to a boil and remove from the heat.

To make “durum”, lay a piece of lavash on a cutting board and spread it with a tablespoon of tomato sauce. Add a handful of meat on top, along with some roasted tomatoes and peppers, and a handful of sumac onions (if using).

Drizzle it with more tomato sauce and gently roll it up from the bottom, tucking the filling in as you go.

Repeat the same process for the remaining lavash bread and doner meat. Using a sharp knife, cut it in half and serve.