Instant Pot Au Gratin is made with potatoes and cauliflower baked in a cheesy, flavor-packed sauce and finished with a golden-brown topping. A delicious side for a festive menu!
This delicious au gratin dish combines ingredients that define comfort – potatoes, cream, cheese. Au gratin hits all the right notes, especially during the colder months. With a gooey, cheesy, sauce that’s packed with flavor – we’re talking paprika, nutmeg, thyme, and gruyere cheese here – this dish is the kind that you’d want to eat just as it comes out of the oven. I love having this dish as a meal by itself, but it also goes perfectly well as a side for a festive menu.
Why this recipe works
- Use the Instant Pot for pre-cooking veggies and making the sauce for the casserole
- Stock is used for cooking the potatoes and cauliflower for increasing flavor
- Delicious crunchy golden crumb on top - so much better than plain Au Gratin!
List of Ingredients
To make this Instant Pot Au Gratin, you will need:
Potatoes: Use Russet potatoes or Yukon Gold, or any variety of potatoes that you prefer. Slice the potatoes thick – if using a mandolin slicer, use the biggest blade.
Cauliflower: I have used cauliflower in this recipe, however, if you like the classic version of Au Gratin, you can skip this, and replace with more potatoes.
Cheese: For the sauce, I have used Gruyere cheese. You can also use Parmesan or Cheddar.
Stock: Use either vegetable or chicken stock
Other ingredients: Butter, Onion, garlic, heavy cream, paprika, nutmeg, thyme, bread crumbs
In this recipe, we cook the potatoes and cauliflower in the Instant Pot, and then make the sauce in the Instant Pot. After assembling the dish and adding the topping, we finish it off by baking it in the oven.
Add 1 cup chicken stock or vegetable stock to the Instant Pot. To this, add the sliced potatoes and cauliflower florets.
Pressure cook the veggies in the Instant Pot for 1 minute on the 'High' setting. Once done, perform a quick release of pressure. Take out the veggies and reserve the stock that's left over.
In the empty Instant Pot, set to 'Saute' mode and add a tablespoon of butter.
Add finely chopped onion (red or white) and minced garlic cloves. Saute until the onions are translucent - for 4- 5 minutes. Hit Cancel on the Instant Pot.
Add 1 cup heavy cream and stir it in. Then add paprika, nutmeg, thyme and stir that in as well.
Add a 1+1/2 teaspoons of all-purpose flour and mix that in to form a smooth sauce. Break up any lumps that may form. You can use a whisk for this.
Add 1 cup grated cheese - I have used Gruyère here, but you can use mozzarella or cheddar as well.
Mix together all the ingredients to form a thick sauce. My sauce was a bit too thick so I thinned it out with some of the reserved stock. You can add more cream at this point if you want a richer sauce.
Grease a baking dish with butter. Add the cooked potatoes and cauliflower.
Pour over the sauce, and keep aside which you prepare the topping.
For the topping, mix together breadcrumbs with some melted butter.
Sprinkle the topping over the filling and bake the dish for 5 minutes at 350 F or 180 C, until the topping is nice and golden brown.
Potatoes and cauliflower: I like making this Instant Pot au gratin with a mix of potatoes and cauliflower. You can choose to skip the cauliflower and use all potatoes. Use Russet potatoes or Yukon Gold. Feel free to add in peas or carrots if you prefer. Slice the potatoes thick – if using a mandolin slicer, use the biggest blade.
Using stock to pre-cook the veggies: Using the Instant Pot, pressure-cook the veggies in chicken or vegetable stock. The stock will be infused in the potatoes and cauliflower, giving it a huge boost of flavor.
Cheese for the sauce: I love using grated Gruyere cheese for the sauce, but you can also use Parmesan or Cheddar or a mix of both. If your sauce is too thick, thin it out with some of the reserved stock.
Make a golden brown topping: I like to give the classic au gratin recipe some extra texture with a delicious golden-brown topping made with bread crumbs. I use melted butter and bread crumbs for the topping , you can also add cheese for added flavor.
An au gratin dish means simply refers to a baked dish with a golden-brown topping. The topping is usually made with breadcrumbs or cheese or a combination of both. In this recipe, we’re going with breadcrumbs mixed with melted butter.
Both Au Gratin and scalloped potatoes have a lot in common, and a few minor differences. While scalloped potatoes are made entirely with potatoes baked in a cream-based sauce, in an Au Gratin, there is cheese in addition to the cream.
This article by The Kitchn explains the differences between the two dishes. Differences aside, both dishes are made with sliced potatoes coated in a delicious sauce, and then finished off by baking in the oven – whichever way you prefer, you are guaranteed to love the results.
More Instant Pot Sides
Instant Pot Au Gratin
- Baking Dish
- For the filling and sauce:
- 1 cup chicken stock can be replaced with vegetable stock
- 4 medium-sized potatoes thickly sliced
- 1/2 small cauliflower cut into florets
- 1 tablespoon butter
- 1 small onion finely chopped
- 4 cloves garlic minced
- 1 cup heavy cream
- 1 teaspoon paprika
- ½ teaspoon nutmeg
- 1 teaspoon thyme
- 1 cup grated cheese use gruyere or cheddar or mozzarella
- For the topping:
- 1/3 cup bread crumbs
- 2 tablespoons butter melted
- Extra butter to grease the baking dish
- Add 1 cup chicken stock or vegetable stock to the Instant Pot.
- Then add the sliced potatoes and cauliflower florets, over the stock.
- Hit the Pressure Cook or Manual button on the Instant Pot and pressure cook the potatoes and cauliflower for 1 minute on the 'High' setting. Once the cooking cycle is complete, perform a quick release of pressure.
- Take out the partially-cooked veggies and reserve the leftover stock.
- In the empty Instant Pot, set to 'Sauté' mode and add a tablespoon of butter.
- Add finely chopped onion and minced garlic cloves.
- Sauté until the onions are translucent - for around 4- 5 minutes. Hit Cancel on the Instant Pot.
- Add 1 cup heavy cream and stir it in. Then add paprika, nutmeg, thyme and stir it into the cream.
- Add a 1+1/2 teaspoons of all-purpose flour and mix it in to form a smooth sauce. Break up any lumps that may form.(You can use a whisk for this).
- Add 1 cup grated cheese.
- Mix together all the ingredients to form a thick sauce. If your sauce is too thick, add some of the reserved stock to thin it out. After cooking the sauce for 3 minutes, turn off the Instant Pot.
- Grease a baking dish with butter. Add the cooked potatoes and cauliflower to the baking dish.
- Pour over the sauce, and keep this aside while you prepare the topping.
For the topping:
- Mix together the breadcrumbs with the melted butter.
- Sprinkle the topping over the filling and bake the dish for 5 minutes at 350 F or 180 C, until the topping is nice and golden brown.
- Preferably, use Russet potatoes or Yukon Gold potatoes. The potatoes have to be sliced thick, if sliced too thin, they will cook too fast in the Instant Pot.
- Use either vegetable stock or chicken stock for cooking the vegetables.
- Gruyere cheese works best for this recipe, but you can also use Parmesan or Cheddar or a mix of both.
- You can add extra Parmesan to the bread crumb topping for more flavor.