Melt 4 tbsp of butter in a large, oven-safe pan over medium low heat. Let the butter get frothy, stirring frequently until you see the milk solids start to brown.

Once you’ve got a lot of brown spec action, add your onions and a big pinch of salt. Cook, stirring occasionally, until the onions have cooked down significantly and become a deep brown color. About 3/4 of the way through the cooking process, add ~ 1/2 cup dry white wine and scrape up any brown bits on the bottom of the pan. The whole process will take an hour to an hour and a half, so be patient!

Melt 1 stick of butter in a pan, brown the butter again, then add 1/2 C flour and stir, cooking for a few minutes to get the raw flour taste out. Then, add your whole milk and bone broth and bring to a simmer. Once at a simmer, your sauce should thicken.

Add about 3/4 of your gruyere, and all your goat cheese and triple cream, and stir till melty and smooth. Season with salt to taste.

Add your freshly grated nutmeg, dijon mustard, and all those delicious caramelized onions and stir to combine.

Parboil your pasta of choice (I boiled for half the time on the box instructions for al dente), reserve some starchy pasta water, and add your pasta to your sauce. If your sauce is too thick, or if you’d like more sauce, add some starchy pasta water to the mix. You can always add, you can’t subtract, so a little at a time is best here. The consistency should be a little looser (almost a bit soupy) than you’ll want your finished product to be, since the pasta will continue to soak up liquid/cook in the oven and as it sits.

Top with remaining shredded gruyere, breadcrumbs and fresh sage and bake at 350 F until the cheese on top is melted and the whole thing is hot and bubbly (about 30 minutes).

Remove from oven, let sit for 10 minutes and enjoy!