I am human, which means I LOVE potatoes au gratin. That is doubly true when I can get them sans lactose.
I have been working on this recipe for a while. Not because making lactose-free mornay (the fancy French way of saying “cheese sauce”) is hard, but because I couldn’t figure out if there was such a thing as too much cheese. I wanted to push the limits of cheesiness to the point where anyone who tried my potatoes au gratin would question whether they had ever really experienced cheese before.
Well, ladies and gentlemen, I am counting this one as a great achievement (if greatness is measured by cheesiness.) In fact, I should probably update my LinkedIn profile.
NOTE: You can layer your potato slices on top of each other in the traditional manner, but this vertical alignment is so much prettier. Also, if you go the layering route, make sure you put mornay and salt and pepper between each layer of potatoes.
NOTE: If you are going to make this recipe, save yourself an hour and use a mandolin. And if you use a mandolin, please, for the love of your fingers, use a safety glove.I consider both to be kitchen essentials. One to make potatoes au gratin, and the other to ensure I have fingers to help me eat potatoes au gratin.
Lactose-Free/Low FODMAP Potatoes Au Gratin
2 lbs of potatoes, trimmed and thinly sliced
salt and pepper
4 tbs butter
4 tbs flour
4 cups lactose-free whole milk
8 oz sharp cheddar cheese, grated
1 cup grated parmesan
1/4 tsp grated nutmeg
1/4 cup chives
Pre-heat oven to 375 degrees.
Organize sliced potatoes vertically in an oven-safe baking dish or your trusty cast iron skillet. Salt and pepper generously. NOTE: ignore this step if you are layering your potatoes lasagna-style.
In a large saucepan, heat butter over medium high heat until it is hot enough that flour will bubble if you sprinkle it into the butter. Add the rest of your flour and whisk constantly, until a thick, golden paste is formed. The paste will then begin to thin until it looks like a cream-colored sauce (it will get lighter in color than when it was a clump because science). Congratulations! You just made a ruex, which is the basis for béchamel, mornay, and many creamy soups!
Add milk a little at a time, whisking constantly. Cook until sauce begins to bubble and turns glossy. It should be able to coat the back of a spoon. This, my friends, is béchamel.
Add cheddar and 1/2 cup of parmesan cheese, a little at a time, whisking constantly to avoid clumps. Add nutmeg and chives. Now you’ve got yourself a mornay! Mornay all day!
Pour cheese sauce over potatoes (or layer with potatoes if you are going for the traditional lasagna-style configuration) and give the pan a good shake to make sure the cheese sauce get all the way down to the bottom of the pan. Top with remaining 1/2 cup of parmesan cheese.
Bake for 45 minutes, then turn the broiler on and cook for 10 more to brown the top.
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