Potatoes Romanoff – a cheesy potato and onion casserole

Potatoes Romanoff is a deliciously creamy potato and onion casserole that’s made with only four ingredients. It tastes so good you would think it should only be served on special occasions, but in reality, it’s so easy to make you can serve it any night of the week!

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A special potato and onion casserole

Potatoes Romanoff might sound like something you would order in a restaurant, but actually, this dish is simply a plain old ordinary potato and onion casserole.

But not just any old potato casserole – this dish is special!

It’s made with only 4 main ingredients – potatoes, onions, double cream, and grated cheese. You can add crushed garlic if you like, or a pinch of cayenne pepper for a kick of heat. And of course, potatoes benefit from being well seasoned with salt and lots of ground black pepper.

• Potatoes Romanoff is made by twice-baking the potatoes for lots of extra creamy goodness. If you are planning to make this dish you will need potatoes that have been baked in their skins and then refrigerated until they are cold. These baked potatoes are grated and mixed with the other ingredients before being baked for a second time until the casserole is golden brown and starting to turn crispy on top.
• The onions are lightly fried until they start to caramelise, and everyone know, caramelisation = extra flavour.
• The cream and the cheese are lightly folded through the potatoes and onions until just combined, leaving the texture of the potato bake light and fluffy.

Potatoes Romanoff is the ideal dish to make when you are feeding a crowd. You can assemble the dish beforehand and leave it in the refrigerator until you are ready to bake it.

I like to make individual portions in little ramekins so that everyone gets their fair share. These ramekins are similar to the ones I used for this recipe. I love them because they are so versatile. They’re great for making individual pot pies and you can even use them for serving soup or chowder.

So without further ado, let’s get on with seeing how to make potatoes Romanoff.

Ingredients

These ingredients will feed 4 people, but you can easily scale this potatoes Romanoff recipe up or down to cater for more or fewer people.

**You can get the complete list of ingredients and full instructions for making this potato and onion casserole on the printable recipe card at the end of this post**

Potatoes – you want to get potatoes that will hold their shape without going soft and powdery. I used Maris Pipers, but you can also use King Edwards, roosters, or russet potatoes.

Onions – I prefer to use white onions in this dish, but if you only have red onions they will work just as well. They should either be grated on the large holes of a box grater or cut in half from tip to root and then sliced into thin semi-circles.

Cream – you should use double cream (or heavy whipping cream) for this dish. As an alternative, you can use thick sour cream. I’ve made this dish many times, using either cream or sour cream, and both are equally delicious.

Grated cheese – I used a mixture of sharp mature cheddar and grated mozzarella because I like the way the mozzarella melts and becomes ‘stretchy’. You can use any cheese that grates well and that you would normally use in cooking.

Cayenne pepper – this adds a touch of heat but is totally optional.

Garlic – (not pictured, and also optional). If you enjoy garlic you can fry one or two cloves of minced garlic with the onions.

Salt and pepper – this is to your own taste. I normally add about half a teaspoon each of both.

Sunflower oil – for frying the onions.

What to do

You will need to plan ahead if you intend to make this potato and onion casserole because you will need cooled, baked potatoes that do take a while to bake in the oven.

If you are in a hurry you can bake the potatoes in the microwave, but once again they will take a while to cool down.

And of course, you can make this dish using leftover baked potatoes. Next time you are making baked potatoes, why not pop a few extra in the oven? You can store them in the refrigerator for a few days and use them to make this dish.

How to bake potatoes

• You can pierce the potatoes a few times with a fork, wrap them in tinfoil and put them into a hot oven for about an hour. Larger potatoes will take longer. The potatoes will be cooked when a fork pierces them easily
• Alternatively, you can microwave them. Pierce the skin with a fork and microwave on high for about 5 minutes. Once again, larger potatoes will take longer. Start testing them after 4 minutes. As soon as you can pierce them easily with a fork they will be ready.
• Whichever method you choose, you should allow the potatoes to cool and then leave them in the refrigerator until you are ready to make this dish.
• You won’t need to salt the potatoes before baking as the seasoning will be added to the dish once it all gets mixed together.

Mix the ingredients

• Grate the cooled baked potatoes on the largest holes of a box grater. There is no need to remove the skin first unless you have an aversion to it. The skin adds to the texture of the finished dish. You will end up with a large piece of skin once the potato has been grated and you can discard this.
• Peel the onions and then grate them on the largest holes of a box grater, or slice them very thinly. You can use a mandolin to do this, or just cut them in half from tip to root and slice them into semi circles using a sharp knife.

• Heat 1 tablespoon of sunflower oil in a frying pan and fry the onions (and crushed garlic if using) gently until they start to soften and take on a little colour. Take your time with this step – let the onions caramelise slowly. If the heat is too high the onions will burn before they are soft. Stir them occasionally as they are frying. This step should take between 5 and 8 minutes.
• Allow the onions to cool.

• Place the grated potato into a mixing bowl and season with salt and pepper (and cayenne pepper if using).
• Add the cooled onions, the cream and the grated cheese.
• Using two forks, mix the ingredients lightly until they are well combined, but not compressed together.

• Transfer the mixture into a large baking dish or into individual ramekins. Pack it in firmly, but try not to compress the mixture too much.
• Bake in a preheated oven (200C / 400F) for 25 to 30 minutes until the top is golden brown (smaller ramekins will take between 20 and 25 minutes).

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Questions

Pin for later

If you would like to try these potatoes Romanoff for yourself, why not pin the recipe to one of your Pinterest boards so you can find it again easily. Just click on the image below.

Other recipes

If you enjoyed these potatoes Romanoff, perhaps you’d like to try some of my other potato recipes:

• Crispy smashed potatos with rosemary
• German fried potatoes – with bacon and onion
• Scalloped potatoes in batter
• Potato and onion bhajis
• Crispy french fries with a spicy coating

The recipe

I have linked this recipe to #CookBlogShare Week 3 2022, run by Sisley and Chloe and hosted by Kate at Gluten Free Alchemist

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