USA Publication & Beetroot, rhubarb + potato gratin
My third book The Modern Cook’s Year will be out in less than a week’s time in the US (March 26th). I’m heading over to NYC for a few days for some events and PR. I am especially excited that I’ll be at the iconic Rizzoli bookstore and hopefully, I’ll see some of you there. I’ll be in conversation with the great Michael Harlan Turkell, award-winning author and host of The Food Seen show on heritage radio.
To celebrate US publication, I wanted to share this recipe from the book – my all-time favourite gratin. There’s gentle comfort from the potatoes and cream, with an unexpected pop of sweet acidity from the rhubarb, a foil for the unrepentant earthiness of the beetroot. The lively warmth of the pink peppercorns tops things off. It’s a pretty beautiful-looking dishful too; there are some amazing colours at play: whites, neon pinks, magenta and the dots of fluoro pink peppercorns – you’d struggle to find one pinker.
I tend not to cook with a lot of dairy but here I make an exception, using the best I can get my hands on. Vegans might try this with almond or oat milk, or even some vegetable stock in place of the creams. I make the stock for this with about half the powder or stock cubes that the packet suggests, so the flavour of the stock doesn’t overwhelm; if you have homemade stock, all the better.
butter, for greasing
1kg potatoes, preferably waxy ones, such as Desiree or Charlotte
500g cooked beetroot (the ones in vacuum packs or home-cooked), peeled
300ml weak vegetable stock (see note above)
300ml double cream 150ml sour cream
2 bay leaves
2 teaspoons pink peppercorns or 1⁄2 teaspoon black peppercorns
200g forced rhubarb, thinly sliced
Preheat the oven to 200oC/180oC fan/gas 6. Butter a large gratin dish.
Peel the potatoes and slice them very finely – a mandoline or the fine slicer attachment on a food processor is the best way to do this; just watch your fingers if you’re using a mandoline. Cut the beetroot into fine slices as well – they don’t have to quite be as thin, so you could cut them with a knife.
Put the stock and both the creams into a large saucepan, along with the bay leaves and 1 teaspoon of the peppercorns. Bring the liquid to just under the boil, then take off the heat and leave to sit for 30 minutes or so. Remove the bay leaves, leaving the peppercorns in, then bring the liquid to just below a simmer. Add the sliced potatoes and cook gently for 5 minutes.
Remove from the heat, season really well with salt and pepper, and spoon half the potatoes into the gratin dish. Put half the beetroot and rhubarb on top, seasoning as you go, then top with the rest of the potatoes and their cream, followed by the rest of the beetroot.
Roughly bash the remaining pink peppercorns in a pestle and mortar and sprinkle on the gratin. Bake for 1 hour, or until the vegetables are completely tender. Cover the top with foil after about 45 minutes if it looks like it is becoming too dark.