I have never put Brussels sprouts in pasta before. I figured that if I regularly make pasta with broccoli and Brussels sprouts are in the same family, why not?! I sliced each sprout in three pieces through the root end. First I sautéed the mushrooms, onions, and garlic. When the pasta was almost done I added the Brussels sprouts, about one half cup pasta water, and a pat of butter. The lid went on the pot and they cooked for a couple of minutes. Then we drained the fusilli and added it to the vegetables along with a little more reserved pasta water. Stir it around and it’s finished except for a sprinkling of cheese. Delicious!