Step 1

Heat a large Dutch oven or a large cast-iron skillet over medium heat. Melt butter and add the olive oil. Add the sliced onions and season with ¼ teaspoon of salt.

Step 2

Cook, stirring often, for 45-50 minutes, or until the onions start to caramelize and have a deep golden brown color. In the beginning, you won't have to stir as frequently.

Step 3

If they start to burn at any point, add a splash of water to bring the temperature down. When the onions start to develop some color (after 30 minutes), turn the heat to high and start stirring every 30 seconds to 1 minute.

Step 4

When the onions have caramelized, add the minced garlic and fresh thyme, and cook for 1 minute, stirring constantly, or until fragrant.

Step 5

Add the flour and stir. Toast for 30 seconds, then deglaze the pan with the white wine and soy sauce. Stir well to get any brow bits off the bottom of the pot. Cook for 1-2 minutes, or until the alcohol evaporates.

Step 6

Add 2 cups of the vegetable broth, and the uncooked pasta, and season with 1/4 tsp of salt, and black pepper.

Step 7

Cook the pasta over medium-low heat, stirring frequently, or until it absorbs most of the liquid. When that happens, add another 2 cups of vegetable broth, and continue cooking until it absorbs most of the liquid. Then, add the final 2 cups and cook until you have a luscious sauce and the pasta is cooked through This will take you roughly 25 minutes, for the pasta to absorb all of the liquid, release starch, and cook through.

Step 8

The best way to tell if the pasta is ready is to taste it. It should be al dente, meaning the pasta should have a slight bite to it and be chewy, but still soft. In the end, turn off the heat and stir the cheese until it melts. Taste and adjust the seasoning if needed, adding more salt and black pepper as needed. Serve!