Preparation

• Bring a large pot of well-salted water to a boil and cook the pasta according to package directions until not quite al dente.
• Meanwhile, cook the bacon in a 12-inch heavy-duty skillet over medium heat, stirring occasionally, until starting to crisp, 4 to 5 minutes. Move the bacon to the side of the skillet, increase the heat to medium high, and add 1 to 2 Tbs. of the oil to coat the pan. When the oil is hot, add the mushrooms, shallots, and 1/4 tsp. salt; cook, stirring occasionally, until the mushrooms release their liquid and start to brown and the shallots just start to caramelize, 4 to 7 minutes. Add the rosemary and pepper flakes, and cook, stirring, until fragrant, about 30 seconds. Stir in the soy sauce; it will evaporate quickly. Remove the pan from the heat and set aside, partially covered, until the pasta is ready.
• Reserve 1 cup of the pasta cooking water. Drain the pasta and add it to the mushroom mixture. Return the skillet to medium-low heat. Add the cheese and 1/2 cup of the pasta water; toss vigorously with tongs for 1 to 2 minutes until a glossy sauce develops, adding a bit more pasta water as needed to loosen the sauce. Season generously with pepper and more salt and pepper flakes to taste. Serve sprinkled with the parsley and more cheese.