Garlic and Parmesan mash
- 2kg/4lb 8oz potatoes, such as Maris Piper, peeled and cut into large equal-sized chunks
- 8 fat garlic cloves, bruised and slightly splintered with the flat side of a wide-bladed knife, then slipped out of their skins
- 2 tsp sea salt flakes, plus extra to taste
- 75g/2½oz unsalted butter, softened
- 50g/1¾oz Parmesan, finely grated
For the optional topping
Put the prepared potatoes and garlic into a very large pan, cover with cold water, add the salt, cover with a lid and bring to the boil over a high heat, then turn down and cook partially covered – just a crack – until very tender.
Put a colander over a large bowl or another pan and drain the potatoes, letting the starchy water collect underneath. Do not throw this away: it is precious liquid (see recipe tip).
Add the butter to the hot, emptied-out potato pan, and let it start melting, then tip in the drained potatoes and garlic. Dip a measuring cup into the cooking liquid, add about 125ml/4fl oz and mash using your chosen method (see recipe tip). You may want to add more of the cooking liquid. I never add less than 250ml/9fl oz, as I like this to be as smooth and creamy as possible, though I’m aware many people prefer a more solid mash. Stir the Parmesan in by hand and check for seasoning before transferring to a warm bowl.
If you are making this in advance, butter a small roasting tin or ovenproof dish, measuring approx. 30x25cm/12x10in, and fill with the mashed potatoes, smoothing down the top. Leave to cool, cover and place in the fridge for up to 3 days.
On reheating, remove from the fridge and allow to come to room temperature, which will take an hour or two, depending on the weather.
Preheat the oven to 200C/180C Fan/Gas 6 and make a crumbly topping by rubbing the breadcrumbs together with the butter and Parmesan, then dot and sprinkle on top. Cook for about 30 minutes, or until piping hot all the way through. Loosely cover the dish with foil if the topping is getting too brown at any stage.
Bizarre though this may sound, I actually have a dedicated electric potato mashing tool (in my defence, I was given it as a present) which makes the potatoes smooth and airy at the same time. You can easily approximate this by giving the potatoes a quick go with an electric hand whisk once you’ve roughly mashed them by hand. But in all cases, the Parmesan must be stirred in by hand at the end. Do not consider using a blender or processor, as both will turn your mash gluey.
It would be criminal of me not to mention that the water the potatoes are cooked in makes the best vegetable soup in the world. I generally make a pea soup with it, cooking a 690g packet of frozen petits pois in just over a litre of potato and garlic stock, until very soft, and then blitzing till smooth with a stick blender. And you don’t have to rush to use it; it’s fine, so long as it’s in the fridge, for up to five days.
While mashed potatoes are always best made at the last minute, you can turn this into an easy make-ahead mash, reformulating it as a gratin.