In a large nonstick skillet over medium-high heat, warm the oil. Add the pancetta and sauté until brown, about 2 minutes. Add the shallots and thyme and sauté until the shallots begin to brown, about 4 minutes. Add the mushrooms, sprinkle with salt and pepper, and sauté until tender, about 5 minutes. Add the broth and simmer until syrupy, about 3 minutes.

Meanwhile, bring a large pot three-fourths full of salted water to a boil. Add the pasta, stir well, and cook until tender, about 7 minutes for dried or 5 minutes for fresh.

Drain the pasta, reserving ½ cup of the cooking liquid. Add the pasta to the mushroom mixture. Stir over medium heat until coated. Mix in the cheese. If too dry, mix in the reserved cooking liquid by ¼ cupfuls. Taste and adjust the seasonings. Divide the pasta between 2 warmed plates. Sprinkle with parsley and serve right away.