French Onion Lasagna

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The holidays are once again upon us and you know what that means. Tis the season for large-format meals designed to feed the unending onslaught of family, friends, and well-wishers. These dishes must be cozy, have broad appeal, and be filling as all get out. If you can achieve all three without going bankrupt, so much the better. So to kick off this cook and bakeathon, I bring you this French Onion Lasagna. A golden and gooey casserole that features layers of homemade pasta, buttery caramelized onions, sharp gruyere cheese, and a velvety béchamel sauce. This is a crowd-pleaser if there ever was one, so let’s get into it. 

I think it goes without saying but I’ll say it anyway – this lasagna is inspired by the classic French Onion soup. Personally, I think French Onion soup is the coziest soup of all time, so I guess you could say this is the coziest lasagna of all time. I’m not going to sugar-coat it, this recipe is a project. It is less of a project if you don’t make your own pasta. But even then you are going to be caramelizing onions for a solid 2-3 hours. So just bear that in mind when you embark on this journey.

Although there is a tone of warning to this fact, I personally don’t see the word “project” and feel deterred. It’s kitchen project season after all. I would much rather spend my time warm in my kitchen with a vat of slow-cooking onions than be out in the snow. Plus, it is perfectly acceptable to invite friends and put them to work. A party might just break out. Trust me on this, I come from the land of kitchen parties.

Okay, let’s start with the pasta. Place equal parts semolina flour and all-purpose flour in a large bowl. You can find semolina flour at most bulk stores. I’ve even spotted it in a handful of regular grocery stores. Add some salt and whisk to combine. Form a well in the center and add 4 yolks and 2 whole eggs. Whisk to combine the eggs and slowly work the dry ingredients into the wet. Once a shaggy dough forms, knead it until the dough is smooth-ish. The dough will feel extremely stiff – this is normal. Gather the dough into a ball and wrap it in plastic wrap. Let rest for 30 minutes. This will allow the flours to hydrate fully and allow the glutens to relax.

While the dough rests, it’s time to cut onions for all eternity. Okay, that is an exaggeration but I am going to ask you to slice 10 good-sized red and yellow onions into half-moons. I like to use a medley of onions, but it’s not necessary. You could use all yellow or all red. Just note the color of your finished caramelized onions may be a little different than mine.

Heat some oil in a large Dutch oven and add the onions and a very generous sprinkling of salt. Add a few sprigs of rosemary and thyme and a few bay leaves. Set the heat to low and cover. Cook for 2-3 hours, stirring the onions every 30 minutes or so. The onions will barely fit in the pot when you start and by the end, they will struggle to clear a quarter of it. It’s seriously magical. 

With the onions on their way, it’s time to prep the remaining components. Take the rested pasta dough and cut it into 8 evenly-sized pieces. Working with a piece at a time, roll the pasta out into sheets. I used the Kitchen Aid pasta maker and I rolled my sheets out to a #4. That was thin enough to be able to see my hand faintly through the pasta sheet. The number may be different on your pasta maker. Transfer the pasta to a large baking sheet lined with parchment paper. Fill the baking sheet with the pasta then place another piece of parchment paper on top. Fill that layer with pasta and continue in this fashion until all the dough is rolled out and stacked. 

Bring a large pot of water up to a boil. It’s time to par-cook the pasta. Since we are using fresh pasta, you can theoretically skip this step, but I feel like it gives the finished lasagna a better texture. We’re not fully cooking the pasta sheets. We’re only going to give them 45 seconds in the boiling water before rinsing them and returning them to the baking sheet in the same stackable fashion. Set the pasta aside.

Now, grab your food processor and add the ricotta, a clove of garlic, an egg, salt, and crushed red pepper flakes. Blitz on high until the ricotta is smooth like velvet. Transfer the cheese to a bowl and set it aside as well. 

And finally, we have the bechamel. This is a very straightforward bechamel. We don’t have to do anything fancy to it because we’ve already got so many bold flavors flying around. Start by making a roux. Melt butter in a large, deep skillet until foamy. Add all-purpose flour and whisk to combine. Continue to cook until the roux emits a warm nutty aroma. Slowly whisk in some dry white wine or vermouth. Once the wine is integrated, gradually add some whole milk to form a creamy sauce. Season it with some Dijon mustard and salt. Simmer until thickened slightly.

Now, it’s time to assemble the lasagna. Start with a thin layer of the bechamel followed by a layer of pasta. Add a third of the caramelized onions and spoon some more of the bechamel over top. Sprinkle with the gruyere cheese and place another layer of pasta on top. Add the ricotta mixture and another layer of pasta. Repeat the onion layer two more times and finish the lasagna with a final layer of pasta and the remaining bechamel. Sprinkle the top with gruyere, torn mozzarella, and buttered panko breadcrumbs. Bake until golden.

And that’s everything you need to know about this French Onion Lasagna. A golden, cheesy delight that will feed a crowd and have them begging for seconds.

Enjoy!