Preheat the oven to 220C, fan-forced. Line an oven tray with baking paper. Finely chop the onion. Heat 2 tsp extra virgin olive oil in a medium frypan over medium-high heat. Cook the onion, stirring regularly, for 4-5 mins until softened. Add the lamb mince to the onion and cook, breaking up the lumps with a spoon, for 3-4 mins until browned.
Step 2 — Finish filling
Add the Spanish seasoning, raisins, half the tomato paste* and 2 tbs water to the mince mixture and cook, stirring, for 1 min. Transfer the lamb mixture to an oven tray and spread out evenly, then set aside to cool (the filling needs to be cool or the pastry will be soggy).
Step 3 — Prep filo stacks
While the lamb filling is cooling, put 1 filo sheet on a bench (keep the remainder covered with a damp tea towel to prevent it drying out). Spray with olive oil. Top with another filo sheet and spray with olive oil. Repeat twice more to make 3 filo stacks.
Step 4 — Roll filo logs
Put one-third of the lamb mixture along the long edge of each filo stack, leaving a 3cm border. Roll up, enclosing the filling, to make 3 logs. (Don't roll the logs too tightly or the filo may split when baked.)
Step 5 — Bake borek
Put 1 filo log on the lined tray and roll, not too tightly, to form a coil. Continue the coil using the remaining filo logs. Spray with olive oil, then scatter over the sesame seeds. Bake for 18-20 mins until golden and crisp.
Step 6 — Get ready to serve
Meanwhile, cut the tomato into wedges. Combine 2 tsp extra virgin olive oil and 2 tsp red wine vinegar in a large bowl and season with salt and pepper. Add the tomato and salad leaves and toss to combine. Cut the borek into wedges. Serve the borek at the table with the salad.