Bring a large pot of salted water to a boil. Add the pasta and cook until just al dente, about 8 minutes. Drain and set aside, saving a cup of pasta water.
While the pasta cooks, heat a large skillet over medium-high heat. Add 2 tablespoons of olive oil and toss in the sliced mushrooms. Sauté until golden and fragrant, about 5-7 minutes, stirring occasionally to develop a rich aroma.
Push the mushrooms to one side of the pan. Add the remaining 1 tablespoon of olive oil if needed, then add the minced garlic. Sauté for 30 seconds until fragrant, stirring quickly to prevent burning and bitterness.
Add the raw shrimp to the pan, seasoning lightly with salt and pepper. Cook for about 2-3 minutes per side until they turn pink, opaque, and firm to the touch, creating a gentle sizzle and aroma of sweetness.
Pour in 1/2 cup of the reserved pasta water and squeeze in the lemon juice. Stir well, allowing the liquid to simmer and thicken slightly, about 2 minutes, creating a glossy, flavorful sauce.
Add the cooked pasta directly into the skillet. Toss gently with tongs to coat the noodles evenly with the sauce, allowing them to absorb the flavors for about 1-2 minutes.
Remove the skillet from heat. Stir in the grated Parmesan and chopped parsley. Taste and adjust seasoning if needed. Serve immediately for the best aroma and texture, garnished with extra lemon zest if desired.