- 2 x 250g/9oz blocks halloumi, cut into 1cm/½in slices
- 200ml/7fl oz buttermilk
- plain flour, for dusting
- vegetable oil, for deep frying
- salt and freshly ground black pepper
- 225g/8oz plain flour
- 1 free-range egg, separated
- 300ml/10½fl oz fridge-cold lager
- 2 large baking potatoes, grated
- salt and freshly ground black pepper
- 2 tbsp vegetable oil
- 50g/1¾oz capers
- 50g/1¾oz gherkins
- 1 tbsp chopped fresh dill
- 1 lemon, juice and zest
- 200ml/7fl oz mayonnaise
- lemon wedges, to serve
- Marinate the halloumi in the buttermilk for at least 20 minutes.
- To make the batter, sift the flour into a large bowl and add the egg yolk. Whisk in the lager gradually and add 125ml/4½oz ice-cold water until well combined.
- Whisk the egg white until stiff peaks form in a separate bowl. Fold the egg whitesinto the batter and chill in the fridge until required.
- Fill a deep-fat fryer or a large, deep, heavy-bottomed pan two-thirds full with vegetable oil. Heat the oil to 180C/350F (use a probe thermometer to check the temperature if you're not using a deep-fat fryer). (CAUTION: Hot oil can be dangerous. Don't leave unattended)
- Shake any excess buttermilk off the halloumi, then dip into the flour and coat in the batter. Fry the halloumi 5 minutes, or until crisp and golden-brown. Remove with a slotted spoon and drain on a baking sheet lined with kitchen paper. Season to taste with salt and freshly ground black pepper.
- For the röstis, boil the potatoes in for 7-8 minutes, then drain. Once cool enough to handle, peel and grate coarsely, and season with salt and freshly ground black pepper.
- Form flat, rounded shapes of the potato mixture and chill in the fridge for 20 mnutes.
- Heat the oil in a frying pan and fry the rostis on a medium heat for 4-5 minutes on each side, or until crisp and golden-brown. Drain on kitchen paper.
- For the tartare sauce, stir the capers, gherkins, dill and lemon in a bowl, add the mayonnaise and mix until well combined.
- Serve the halloumi on top of a rosti with a spoonful of tartare sauce and a lemon wedge on the side.