Bring a large pot of salted water to a rapid boil. Once boiling, add the spaghetti. Cook according to package instructions until al dente (about 8-10 minutes).

While the pasta is cooking, slice garlic thinly and finely chop parsley. Clean and slice the mushrooms.

Before draining the pasta, reserve 1 cup of pasta cooking water.

In a large skillet, heat 2 tablespoons of olive oil over medium-high heat. Add sliced mushrooms and sauté until golden and slightly crispy (about 5-7 minutes). Remove mushrooms and set aside.

In the same skillet, reduce heat and add remaining olive oil and sliced garlic. Cook until garlic turns light golden brown.

Add chili flakes to the skillet and pour in reserved pasta water. Return sautéed mushrooms and simmer.

Toss the drained spaghetti into the skillet, coating it with the mushroom-garlic sauce. Cook for an additional 1-2 minutes.

Transfer to serving plates and top with grated parmesan, fresh parsley, and lemon zest.