Preheat your oven to 200°C (400°F) and prepare a baking tray lined with parchment paper.

In a food processor, combine the ground beef, grated onion, minced garlic, paprika, oregano, salt, and black pepper. Process until smooth and sticky.

Transfer half of the meat mixture onto the parchment, shape into a thin rectangle, then roll tightly into a log. Repeat with the remaining mixture.

Place both kebab logs onto the baking tray with chopped tomatoes and green peppers. Bake for about 30 minutes until cooked through.

Remove parchment and, if desired, slice thinly. Broil for an additional 3-5 minutes until crisp.

While kebabs are broiling, whisk together mayonnaise and sour cream for the garlic sauce and toss red onions with sumac.

Assemble your kebabs in pita or flatbread with roasted veggies and garlic sauce.