Salt-crust baked potatoes with smoked potato purée
Baking in a salt-crust casing insulates the baked potatoes, cooking gently and evenly.
Ingredients
For the salt pastry
- 225g/8oz plain flour, plus extra for dusting
- 150g/5½oz table salt
- 1 free-range egg white
For the baked potatoes
- 4 large Jersey Royal potatoes (each weighing around 100²µ/3½´Ç³ú), scrubbed
- 12 shavings Parmesan or Gouda-style hard cheese
- 1 tbsp small capers, to garnish
- 1 tbsp snipped fresh chives, to garnish
For the smoked potato purée
- 2 large Maris Piper potatoes, scrubbed
- 100ml/3½fl oz smoked oil
- 55g/2oz grated Parmesan or Gouda-style hard cheese
- 55g/2oz unsalted butter
- 100ml/3½fl oz milk
- salt and freshly ground black pepper
For the onion oil
- 25g/1oz spring onion tops
- 25g/1oz chives
- 200g/7fl oz pomace oil
For the pickled shallots
- 100ml/3½fl oz white wine vinegar
- 100²µ/3½´Ç³ú caster sugar
- 2 banana shallots, thickly sliced
For the crispy shallots
For the onion ash
- 1 onion, thinly sliced
Method
For the salt pastry, mix the flour and salt together in a bowl. Add the egg white and 125ml/4fl oz of water and stir well until the mixture comes together as a dough. Continue to stir or knead the mixture until you get a soft, smooth dough. If you have time, leave to chill in the fridge. Roll the dough out on a lightly floured work surface until it is about 5mm thick. Preheat the oven to 200C/180C/Gas 6.
For the baked potatoes, wrap each potato individually in the salt pastry so they are completely encased. Place on a foil-lined baking tray and bake in the preheated oven for 45 minutes. Allow to cool slightly before cracking open the pastry and removing the potatoes. Leave the oven on.
Cut a cross in the top of each potato and squeeze to open and expose the flesh. Add three cheese shavings onto each potato and place back in the oven for 2 minutes.
Meanwhile, for the smoked potato purée, bake the potatoes in the oven for 60 minutes, or until soft. Cut each potato in half and scoop out the flesh. Pass through a fine potato ricer and place in a saucepan. Add the oil, cheese and butter and stir gently over a low heat until everything is melted. Remove from the heat and add the milk. Season with salt and pepper.
For the onion oil, blend all of the ingredients in a food processor until smooth. Place in a saucepan and heat, whisking continuously, until very hot. Leave to cool completely and then pour through muslin cloth into a bowl underneath. Transfer the oil to a small bowl until ready to serve.
For the pickled shallots, bring the vinegar and sugar to the boil in a small saucepan. Add the shallots to the pan, remove from the heat and leave to cool and infuse.
For the crispy shallots, preheat some oil in a deep saucepan to a temperature of 140C. (CAUTION: hot oil can be dangerous. Do not leave unattended.) Dust the shallots with the cornflour and deep-fry until golden brown. Carefully transfer using a slotted spoon to absorbent kitchen paper and season lightly with salt.
For the onion ash, place the onion slices under a medium grill and cook until deeply caramelized. Place in a pestle and mortar and crush until a coarse powder forms.
To serve, place some of the smoked potato purée in the centre of each plate. Add a salt-baked potato on top, followed by a spoonful of onion oil over each potato. Reserve any leftover onion oil to use in another recipe. Add a generous pinch of onion ash, some of the pickled shallots and some capers on top of each potato. Finish the dish with crispy shallots and chives.