Think of the creamiest, cheesiest mac and cheese you've ever had. Now, instead of noodles, imagine that sauce on potatoes! In this ultra cheesy potato gratin recipe, that's exactly what you get: the cheesy potatoes of your dreams that make the perfect holiday side dish.
Whether you call them potatoes au gratin, au gratin potatoes, or just potato gratin, they're cheesy, they're potatoes, and they're delicious!
What makes them different from scalloped potatoes is the addition of cheese. And what doesn't get better with cheese?
Now, if you're here, you might be on the lookout for Thanksgiving or Christmas recipes amidst a million other things you need to do. You've got a LOT going on this time of year. So let's skip the small talk and dive into the details.
Cheesy potato gratin ingredients
Here's what you'll need to create these mac and cheese-like potatoes for yourself!
- Large Yukon gold or russet potatoes (I use four large potatoes, about 900 g)
- Diced white onion
- Unsalted butter
- Salt and pepper
- Garlic cloves
- Whipping cream (I use cream because you get a richer, creamier result than with just milk!)
- Freshly shredded old/sharp cheddar cheese (don't use pre-shredded cheese, here's why)
- Mustard powder
- Garlic powder
- Onion powder
- ¼ cup finely shredded parmesan (optional)
- A sprinkle of parsley for garnish (optional but adds great colour!)
With the help of a mandolin slicer, this is a reeeeeally easy recipe! Just practice patience while you add the cream to the roux (if you add it too fast, the sauce won't come together as nicely), and follow the rest of my instructions.
How to make my ultra cheesy potato gratin for yourself
- Begin by turning your oven on to 350 F.
- Now start melting butter in a large skillet on medium heat WITH the diced onions and minced garlic cloves.
- Once the butter is melted and the onions have softened, whisk in the flour, salt and pepper, mustard powder, onion powder, and garlic powder until it forms a paste–this takes about one minute.
- SLOWLY add the cream to the mixture a bit at a time. Keep whisking as you add the cream. It will thicken up as you go–spend at least five minutes on this.
- Once all of the cream is added, turn the heat to low and add the freshly shredded cheese into the mixture. Let the heat of the roux begin to melt the cheese. Don't stir too much or it will get stringy.
- Now it's time for washing, drying, and PEELING your potatoes before you slice them thinly with a mandolin (like this one).
(Unless you're incredibly patient and skilled with a knife, getting them thin enough with just a knife will be really tough.)
- Slice your potatoes into slices between ⅛ and ¼-inch thick. If they're not thin enough, they won't cook in time.
- Add your sliced potatoes to a large bowl. Toss with additional salt and pepper, to taste.
- Grease an 8x8 oven-safe dish.
- Add half of the sliced potatoes to the dish, laying as flat as possible. Top with half of the sauce.
- Add the rest of the potatoes on top, keeping them as flat as possible. Top with the rest of the cheese sauce.
- Now cover the cheesy potato gratin with tin foil and place in the oven.
- Cook for 60 minutes, and remove from oven but keep oven on. If using parmesan, add it now. Return the potato gratin to the oven WITHOUT tin foil. Cook for another 15 minutes (75 minutes total).
Other vegetarian holiday recipes
One last thing before the specifics, here are some other vegetarian recipes for Christmas, Thanksgiving, Easter, etc. to check out:
CHRISTMAS COOKIES: OATMEAL COOKIES W/ WHITE CHOCOLATE CHIPS & CRANBERRIES
THE BEST VEGETARIAN CHRISTMAS APPETIZERS
EASY CHEESY SCORED BAKED POTATOES
Cheesy Potato Gratin
Ultra Cheesy Potato Gratin: The Perfect Vegetarian Side Dish
- 1 cup white onion finely diced
- 2 cloves garlic minced
- 3 tablespoon unsalted butter 42 g
- 3 tablespoon all-purpose flour
- ½ teaspoon mustard powder
- ½ teaspoon garlic powder
- ½ teaspoon onion powder
- ½ teaspoon salt or more, to taste
- black pepper to taste
- 2 cups whipping cream
- 1.5 cups sharp cheddar cheese shredded from a block, not pre-shredded
- 900 g Yukon gold or russet potatoes about four large potatoes, sliced to ⅛ to ¼-inch thick with a mandolin
- ¼ cup parmesan cheese optional, finely grated
- parsley optional, for garnish
- Heat your oven to 350 F. Grease an 8x8 dish and set aside.
- Melt butter in a large skillet on medium heat WITH the diced onions and minced garlic.Once the butter is melted and the onions have softened, whisk in the flour, salt and pepper, mustard powder, onion powder, and garlic powder until it forms a paste. (This takes about one minute)
- SLOWLY add the cream to the mixture a bit at a time. Keep whisking as you add the cream. It will thicken up as you go. Spend at least five minutes on this.
- Once all of the cream is added, turn the heat to low and add the freshly shredded cheese into the mixture. Let the heat of the roux begin to melt the cheese.*Once the cheese is melted and your sauce is done, remove from heat and set aside.
- Wash, dry, and peel your potatoes. Slice your potatoes into slices between ⅛ and ¼-inch thick.**Add your sliced potatoes to a large bowl. Toss with additional salt and pepper, to taste.
- Add half of the sliced potatoes to the greased dish, laying as flat as possible. Top with half of the cheese sauce. Now add the rest of the potatoes on top, keeping them as flat as possible. Top with the rest of the cheese sauce.
- Cover the dish with tin foil and bake for 60 minutes. Remove the tin foil and add the shredded parmesan (if using). Cook for another 15 minutes, or until bubbly and golden. You can test the potatoes with a fork and make sure a fork goes in easily.
- Let the potato gratin stand for at least 15 minutes before serving – it will be hot! Top with fresh or dried parsley for garnish.
There you have it!
Happy holidays or happy regular dinner! No matter the occasion, I hope you just love this ultra cheesy potato gratin.
Did this with radishes. Delish. And way less carbs. Thank you for a scrumptious recipe!