12 oz. hen-of-the-woods (maitake) mushrooms, pulled into thin strips
2 large shallots, halved lengthwise, then peeled and very thinly sliced
Olive oil cooking spray (preferably nonaerosol)
Salt and freshly ground black pepper
2 tbsp. chopped fresh thyme
½ lb. meaty guanciale or pancetta or smoked pancetta
1 tbsp. EVOO
1 lb. spaghetti
1 cup grated Pecorino Romano
Zest of 1 lemon
Arrange a rack in the upper third of the oven; preheat to 475°. Line a large baking sheet with foil; top with parchment. Arrange the mushrooms and shallots on the baking sheet in a single layer. Spray evenly and liberally with the cooking spray and season generously with salt and pepper. Sprinkle the vegetables with the thyme. Roast, stirring halfway through cooking, until the mushrooms are crispy and fragrant, about 20 minutes.
Place the guanciale in the freezer for 10 minutes. Once it’s firm, slice it into thin 1/2-inch-long pieces.
Meanwhile, bring a large pot of water to boil for the pasta.
Heat a large skillet over medium low heat. Add the EVOO, one turn of the pan, then add the guanciale. Cook until the fat renders, about 15 minutes. Season with pepper and remove from the heat.
Salt the boiling water, add the pasta, and cook for a minute or two less than the package instructions. Reserve 1½ cups of the cooking water, then drain the pasta.
Add the pasta, half the cheese, and ¾ cup pasta water to the skillet. Toss the pasta for 1 minute to coat, adding more pasta water if needed to thin the sauce. Transfer the pasta to a large bowl and top with the remaining cheese, a pile of crispy mushrooms and shallots, and a little lemon zest.