Easy and Cheesy Sourdough Au Gratin Potatoes Recipe
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Perfectly creamy, cheesy, and flavorful, these are Sourdough Au Gratin Potatoes at their very best! Sourdough discard is used to thicken the cream sauce. Cover and bake for the most tender and cheesy potatoes – perfect for any holiday table.
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Looking for the perfect side dish to elevate your holiday table? Look no further than this creamy Sourdough Au Gratin Potatoes recipe!
Potatoes Au Gratin, also known as cheesy potatoes, take the humble potato to new heights with their rich flavor and irresistible cheesy goodness.
This great recipe features thinly sliced potatoes layered with a creamy, indulgent sauce thickened with sourdough discard and a generous amount of cheese. The result? A mouthwatering dish that is sure to impress your guests.
Whether you’re serving a crowd or simply craving a comforting, cheesy sourdough potato gratin, this dish is a must-try. Get ready to dive into layers of creamy Sourdough Au Gratin Potatoes that will steal the show at any meal.
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Why You’ll Love This Recipe:
Easy
Besides slicing the potatoes, Sourdough Au Gratin Potatoes are a quick and easy side dish to prepare! Better yet, your guests will think you labored tirelessly to prepare it and rave over each delicious bite!
Flavor
What’s not to love about tender slices of potatoes smothered in a luscious cheese sauce, baked until golden brown with a slight cheese crust on top? Then take it up another notch and add sourdough discard? It’s absolutely delicious.
Great Use for Discard
Did you know that sourdough discard is a fabulous thickening agent? Instead of fussing around with making a roux, simply add sourdough discard to your liquid and watch it thicken up! I use this exact cooking trick to make my delicious creamy and cheese Sourdough Mac and Cheese as well.
Ingredients
Potatoes – The best potatoes for Sourdough Au Gratin are waxy potatoes like Yukon gold or red potatoes. Unlike Russet potatoes, these delicious potatoes are fabulous at keeping their shape and not turning to mush after being baked. Instead, you will find tender potatoes for each bite. Plus, peeling is optional with these potatoes!
Small Onion – Thin slices of onion bring great bite and flavor to this Sourdough Au Gratin Potatoes.
Dairy – For a smooth and creamy sauce, I used whole milk and heavy cream.
Sourdough Starter Discard – Instead of creating a roux of all-purpose flour and butter to thicken your cheese sauce, use sourdough discard! It will make the cream sauce so luscious, with a tiny hint of tang. Plus it’s an easy way to use up any extra sourdough discard.
Cheese – Sharp cheddar cheese, Gruyere, and Parmesan cheese bring a robust flavor to this cheese sauce. However, you can opt for just one type of cheese or substitute with others like white cheddar or asiago cheese.
Seasoning – Salt and black pepper to taste plus garlic powder bring delicious flavor to this easy side dish. However, fresh thyme leaves or roasted garlic cloves would be great additions.
Supplies
Sharp knife, Food processor, or Mandoline
Cutting Board
Medium Saucepan
Cheese Grater
Whisk
Wooden Spoon
2 1/2 – 3 quart casserole dish
How to Make Sourdough Au Gratin Potatoes
Preheat your oven to 400 degrees F. Grease a 2.5 – 3 quart casserole dish with butter and set aside.
First, scrub the potatoes (peeling is optional!) and thinly slice them into 1/8-inch thick slices. You could also use a food processor or mandoline for quick work of slicing. Slice half of a small onion as thin as possible. Add the sliced potatoes and onions to a large bowl and set aside.
In a medium bowl, whisk together the milk, heavy cream, and sourdough discard until smooth. Pour the mixture into a medium saucepan and heat to medium heat. Stir occasionally. Continue to cook until the sauce thickens and begins to bubble. Remove from the heat.
To the white sauce, add the cheddar cheese, 1/2 cup of the gruyere cheese, garlic powder, and salt and pepper to taste. Stir until the cheese is fully melted and smooth.
Pour the cheese sauce over the sliced potatoes and onion. With a wooden spoon, stir until the vegetables are fully coated in the cheese sauce.
Pour the potato mixture into the prepared baking dish and spread evenly in a single layer. Top the potatoes with the remaining gruyere and Parmesan cheese, then cover the baking dish with aluminum foil and place in the preheated oven to bake for 60 minutes.
Next, remove the foil and continue to cook for an additional 15-30 minutes or until the topping is golden brown and the potatoes can be easily pierced with a fork.
Allow the Sourdough Au Gratin to rest for 15 minutes before serving. Garnish with chopped parsley, chives, or thyme leaves, and serve warm!
How to Serve
Sourdough Au Gratin is the perfect side dish for any special occasion, like Easter or Christmas dinner. Serve this creamy and delicious potato recipe alongside a salty slice of honey ham or a juicy cut of prime rib for an exceptional dining experience. Don’t forget to pass the Sourdough Dinner Rolls!
How to Store
Store leftover Sourdough Au Gratin in an airtight container in the fridge for up to 4-5 days.
To reheat, place the casserole dish covered in foil in a 350-degree oven for about 15-20 minutes, or until heated throughout.
FAQs:
What is the difference between Scalloped Potatoes and Au Gratin Potatoes?
While both are popular potato dishes, the main difference between scalloped potatoes and au gratin potatoes is the inclusion of cheese. Scalloped Potatoes are a creamy and tender baked potato dish, while Au Gratin Potatoes are covered in a cheesy, cream sauce with a crispy cheese crust on top.
Can I use different types of cheeses for Sourdough Au Gratin?
This Sourdough Au Gratin recipe uses a combination of cheeses like Cheddar Cheese, Gruyere cheese, and Parmesan cheese. If preferred, you could use only one type of cheese for the whole dish or substitute it with other delicious grated cheeses, like white cheddar cheese or asiago.
Can Sourdough Au Gratin be made in advance?
Not only is this potato side dish easy and delicious but it can also be made in advance! Save yourself some time by preparing the creamy potatoes up to 24 hours in advance. Prepare the recipe until it’s ready to bake. Instead, cover the baking dish with aluminum foil and store it in the fridge. Bake for an additional 10-15 minutes than the original recipe.
Happy cooking!
More Recipes Like This:
Homemade Fried Sourdough Chicken Tenders
Sourdough Mac and Cheese with Sourdough Breadcrumb Topping
Sourdough Au Gratin Potatoes Recipe
Perfectly creamy, cheesy, and flavorful, these are Sourdough Au Gratin Potatoes at their very best! Sourdough discard is used to thicken the cream sauce. Cover and bake for the most tender and cheesy potatoes - perfect for any holiday table.
Enter your email below, and we’ll send it straight to your inbox! Plus, you’ll get my newest sourdough recipes and best tips every week!
Ingredients
- 2 1/2 pounds Gold Yukon Potatoes (about 6-7), 1/8-inch slices
- 1/2 small onion (about 1/2 cup), thinly sliced
- 2 cups whole milk (470g)
- 1/2 cup heavy cream (100g)
- 1/4 cup sourdough discard (70g)
- 1 cup cheddar cheese (113g or 4 oz), shredded
- 1 cup Gruyere cheese (120g), shredded
- 1/4 cup Parmesan cheese (20g)
- 1/2 teaspoon garlic powder
- salt and pepper, to taste
Instructions
1. Preheat your oven to 400 degrees F. Grease a 2.5 - 3 quart casserole dish with butter and set aside.
2. First, scrub 2 1/2 pounds of potatoes (peeling is optional!) and thinly slice them into 1/8-inch thick slices. You could also use a food processor or mandoline for quick work of slicing. Slice half of a small onion (about 1/2 cup) as thin as possible. Add the sliced potatoes and onions to a large bowl and set aside.
3. In a medium bowl, whisk together 2 c (470g) milk, 1/2 c (100g) heavy cream, and 1/4 c (70g) sourdough discard until smooth. Pour the mixture into a medium saucepan and heat to medium heat. Stir occasionally. Continue to cook until the sauce thickens and begins to bubble. Remove from the heat.
4. To the white sauce, add 1 c (113g or 4 oz) grated cheddar cheese, 1/2 cup (60g) of the grated Gruyere cheese, 1/2 tsp garlic powder, and salt and pepper to taste. Stir until the cheese is fully melted and smooth.
5. Pour the cheese sauce over the sliced potatoes and onion. With a wooden spoon, stir until the vegetables are fully coated in the cheese sauce.
6. Pour the potato mixture into the prepared baking dish and spread evenly in a single layer. Top the potatoes with the remaining 1/2 c (60g) grated Gruyere and 1/4 c (20g) grated Parmesan cheese, then cover the baking dish with aluminum foil and place in the preheated oven to bake for 60 minutes.
7. Next, remove the foil and continue to cook for an additional 15-30 minutes or until the topping is golden brown and the potatoes can be easily pierced with a fork.
8. Allow the Sourdough Au Gratin to rest for 15 minutes before serving. Garnish with chopped parsley, chives, or thyme leaves, and serve warm!
Notes
How to Serve
Sourdough Au Gratin is the perfect side dish for any special occasion, like Easter or Christmas dinner. Serve this creamy and delicious potato recipe alongside a salty slice of honey ham or a juicy cut of prime rib for an exceptional dining experience. Don't forget to pass the Sourdough Dinner Rolls!
How to Store
Store leftover Sourdough Au Gratin in an airtight container in the fridge for up to 4-5 days.
To reheat, place the casserole dish covered in foil in a 350-degree oven for about 15-20 minutes, or until heated throughout.
FAQs:
What is the difference between Scalloped Potatoes and Au Gratin Potatoes?
While both are popular potato dishes, the main difference between scalloped potatoes and au gratin potatoes is the inclusion of cheese. Scalloped Potatoes are a creamy and tender baked potato dish, while Au Gratin Potatoes are covered in a cheesy, cream sauce with a crispy cheese crust on top.
Can I use different types of cheeses for Sourdough Au Gratin?
This Sourdough Au Gratin recipe uses a combination of cheeses like Cheddar Cheese, Gruyere cheese, and Parmesan cheese. If preferred, you could use only one type of cheese for the whole dish or substitute it with other delicious grated cheeses, like white cheddar cheese or asiago.
Can Sourdough Au Gratin be made in advance?
Not only is this potato side dish easy and delicious but it can also be made in advance! Save yourself some time by preparing the creamy potatoes up to 24 hours in advance. Prepare the recipe until it's ready to bake. Instead, cover the baking dish with aluminum foil and store it in the fridge. Bake for an additional 10-15 minutes than the original recipe.
Wow! I was so excited to use my starter – these potatoes do not disappoint!
The sauce thickened beautifully from it. They deliciously completed our Easter dinner!
I’m so thrilled to hear that you enjoyed this recipe! I love how easy and delicious it is to make. Thank you for sharing!
My family devoured every last bit of this dish! It will be a favorite from now on. Thank you!