In a large bowl, add the beef mince.
Add the grated and strained onion, tomato paste, all the spices, ginger garlic paste, and chopped coriander.
Mix everything thoroughly using your hands until the mixture is well combined and slightly sticky. This helps the kebabs hold together and stay juicy.
Let the mixture rest for 10–15 minutes to allow the flavours to develop.
Preheat the oven to 200°C.
Line a large baking tray with parchment paper or lightly grease it.
Spread the kebab mixture evenly onto the tray, pressing it down into a flat, even layer about 1–1.5 cm thick.
Place the halved tomatoes cut-side up around the kebab mixture on the same tray.
Drizzle everything lightly with olive oil.
Bake for 18–22 minutes, or until the kebab is fully cooked and lightly browned on top.
Remove the tray from the oven.
Peel the skins off the roasted tomatoes (they should come off easily).
Mash the tomatoes with a fork and season with a little salt and pepper.
Set aside, this becomes a juicy, flavour-packed layer for the sandwich.
In a small bowl, combine Greek yogurt, mayonnaise, crushed garlic, lemon juice, olive oil, sumac, salt, and pepper.
Mix until smooth and creamy. Adjust seasoning to taste.
Slice the baguettes lengthwise and lightly toast if desired.
Spread a generous layer of garlic yogurt sauce on the base.
Add a thin layer of tomato sauce.
Spoon over the mashed roasted tomatoes.
Cut the sheet pan kebab into strips and layer generously into the baguette.
Top with cucumber, lettuce, and fresh tomato slices.
Finish with a drizzle of pomegranate molasses for a sweet-tangy contrast.
Close the sandwich, slice, and serve.