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Fresh sprigs of sage, rosemary and thyme flavor the homemade cream sauce for theses potatoes au gratin. This comforting cheesy potatoes casserole is perfect with ham, turkey or roast beef.
Cheesy potatoes are versatile. You can make them in a casserole, in the slow cooker or even in the Instant Pot. But there is something classic and comforting about scalloped style potatoes au gratin with shredded cheese and creamy sauce. This recipe uses fresh herbs such as rosemary to deepen the flavor and make them unique.
We’ve shared so many of our best potato recipes, but these savory potatoes au gratin take traditional potatoes to a new level. I LOVE fresh herbs…and sage, rosemary and thyme are three of my favorites (I even love the dried version of these!). They add such a mouthwatering richness to recipes. So why not infuse the white cream sauce with these fresh herbs? These would be great for your holiday dinners and are sure to impress.
Scalloped potatoes both start with potato slices and a white cream sauce. The difference comes in that au gratin potatoes also have shredded cheese between the layers of potatoes. Au gratin potatoes will also often have a layer of bread crumbs baked on top. Our recipe skips that step, but feel free to add it if you’d like.
The type of potatoes you use will depend on the type of casserole you are after. If you like a creamier casserole, use Russet potatoes. They are high in starch and will break apart slightly causing the sauce to be creamy.
If you’d like the potatoes to hold their shape, use red potatoes or Yukon gold potatoes. They are low starch and hold up to baking.
If you want to quickly and easily make perfectly sliced au gratin potatoes, there is one tool you need: a mandolin slicer. This tool has an adjustable blade that you push a potato back and forth on to cut slices. It works beautifully and easily. It is so much quicker than using a knife and you just the thickness of slices that you want!
**Need a mandolin slicer? This is the one we have. It’s also great for other vegetables.**
Potatoes au gratin should be sliced very thin, about 1/8″. Sometimes we make ours 1/4″ thick. The thickness of the potato slices will affect the baking time, so it is best to slice them thin.
Sometimes high heat can make the cheesy sauce look curdled. Although it doesn’t look pretty, the potatoes are safe to eat. For best results, prepare the smooth sauce as directed in this recipe, then drizzle it over the potatoes and cover to bake.
Yes! There are 2 ways to do this. One way is to just slice the potatoes in advance. After you’ve sliced the potatoes, cover them completely with water so that they don’t turn brown overnight. Drain off the potatoes before continuing with the casserole the next day.
If you need to completely make it in advance, it is best to bake the potatoes as the recipe states, then allow them to cool completely. Cover with foil and refrigerate overnight.
To reheat, bake the covered casserole for 20-30 minutes in a 350 degree F oven.
Heat the oven to 350 degrees Fahrenheit. Cover the casserole dish with foil and heat for about 20-25 minutes (the exact timing will depend on the dish you are using and how many potatoes there are).
The potatoes should be bubbling around the edges and heated through.