Mary Berry Dauphinoise Potatoes​

Mary Berry’s dauphinoise potatoes layer two kinds of potato, sweet and King Edward, in cream and stock under a Parmesan crust. The result is soft, savoury and just rich enough, with the sweet potato adding colour and a mellow edge. It bakes at a hot 220C and takes about an hour and five minutes, serving six to eight.

She calls it a Really Good Double Potato Dauphinoise in Mary Berry’s Family Sunday Lunches (2016), and the double potato is the clever part. Most dauphinoise uses one waxy potato drowned in cream, but Berry pairs floury King Edwards with sweet potato and cuts the cream with stock. That’s why hers tastes lighter and less claggy than the usual version.

The one thing that ruins a dauphinoise is a slice left poking above the liquid. Berry slices the potatoes very thinly, then says to push them down into the liquid with your hands so they’re all covered. Any slice above the surface dries into a hard, leathery edge while the rest turns tender.

Mary Berry Dauphinoise Potatoes​

Recipe by Pinch PerfectCourse: DinnerCuisine: BritishDifficulty: Easy

Servings

6-8

servings

Prep time

20

minutes

Cooking time

1

hour 

Calories

350

kcal

From Mary Berry’s Family Sunday Lunches (2016). A two-potato take on the French classic, lightened with stock, built for a roast and best cooked in one go rather than reheated from raw.

Ingredients

• 750g (1lb 10oz) sweet potatoes, peeled

• 750g (1lb 10oz) King Edward potatoes, peeled

• 300ml (½ pint) double cream

• 150ml (¼ pint) chicken or vegetable stock

• 50g (2oz) Parmesan cheese, grated

• salt and freshly ground black pepper

Directions

• Preheat: Preheat the oven to 220°C/Fan 200°C/Gas 7. You will need a 2-2.4 litre (3½-4 pint) shallow ovenproof dish, buttered.
• Slice: Slice the sweet potatoes and King Edwards very thinly using a sharp knife or the slicing blade on a processor.
• Layer: Arrange one layer of mixed potatoes in the buttered dish. Season with salt and pepper and drizzle over a little cream and stock. Continue to layer the potatoes and cream and stock until you have used all the ingredients. Push the potatoes down into the liquid using your hands so they are all covered.
• Top and cover: Sprinkle with the cheese and cover with foil.
• Bake: Bake in the preheated oven for about 40 minutes. Remove the foil and continue to cook for another 25-30 minutes, or until golden brown and the potatoes are cooked through.
• Rest: Leave to stand for 5 minutes before serving.

FAQs

Can I make dauphinoise potatoes ahead of time?

Not from raw, and Berry is clear on why: sliced potatoes turn brown if they sit uncooked, so you cook this in one go. What you can do is part-cook it for about 45 minutes up to 24 hours ahead, then reheat at 180°C/Fan 160°C/Gas 4 for 20-30 minutes until piping hot. It also freezes well once fully cooked, which the raw slices never would.

Why does Berry mix sweet potato and King Edward?

The King Edward is a floury potato that holds structure and soaks up the cream, while the sweet potato brings colour and a soft, mellow flavour. Together they stop the dish being one heavy note, which is Berry’s whole reason for calling it a “double” dauphinoise. The two cook at a similar rate once sliced thinly, so neither turns to mush.

Can I use only regular potatoes and skip the sweet potato?

Yes, use 1.5kg of King Edwards or another floury variety like Maris Piper if you want a classic all-white dauphinoise. You’ll lose the colour and the gentle sweetness, so add a little extra seasoning to make up for it. Avoid waxy salad potatoes, since they stay firm and won’t drink in the cream the way a floury potato does.

Why cut the cream with stock instead of using all cream?

The 150ml of stock against 300ml of cream keeps the dish rich without tipping into heavy, which matters when it sits beside a roast. Straight cream can set claggy and coat your mouth, whereas the stock loosens it and adds savoury depth. It’s the same instinct behind serving this with something rich like her salmon en croûte, where you don’t want two heavy elements fighting.

What should I serve dauphinoise potatoes with?

Berry suggests them for a Sunday lunch, and she points to duck in particular since the sweet potato flatters it. They work under any roast meat or a fish main, and hold their own next to her salmon en croûte for a smarter dinner. Start the meal light with something like her smoked salmon starter so the potatoes aren’t competing with a heavy first course.

Do I really need to cover it with foil first?

Yes, the foil traps steam so the thick bed of potato cooks through before the top colours. Take it off for the final 25-30 minutes and the Parmesan browns into that golden crust. Skip the foil and you get a scorched top over slices that are still hard underneath, which is the most common dauphinoise mistake.