Tepsi kebap with spinach yoghurt

For the tepsi kebap

• 500g/1lb 2oz lamb mince, about 20 per cent fat

• 1 onion, minced in a food processor and drained of any liquid or very finely chopped

• 2 large garlic cloves, minced

• ½ red pepper, cored, seeds removed and very finely chopped

• 50g/1¾oz fresh flatleaf parsley, leaves and stems finely chopped, plus extra leaves to serve

• 2 tbsp tomato purée

• 1 tbsp pul biber or Aleppo chilli flakes

• ½ tsp bicarbonate of soda

• sea salt flakes and freshly ground black pepper

For the spinach yoghurt

• 250g/9oz spinach

• 500g/1lb 2oz Greek-style yoghurt

• 1 large garlic clove, minced

• 2 generous handfuls walnut halves, roughly chopped

• 2 tsp sumac, plus extra to garnish

• olive oil, for drizzling

• sea salt flakes and freshly ground black pepper

To serve (optional)

• tortilla wraps or bread

• sliced red onion

• Greek-style yoghurt