Fill a large pot with salted water and bring to a boil. Cook the spaghetti until al dente, about 8-10 minutes, and reserve 1 cup of pasta water.

In a large skillet, heat 1 tablespoon of olive oil over medium-high heat. Add the mushrooms and sauté until golden and tender, about 5-7 minutes.

Reduce heat to low, add remaining olive oil and garlic, cooking until fragrant and lightly golden, about 1 minute.

Stir in the chilli flakes and reserved pasta water, seasoning with salt. Simmer for 2-3 minutes.

Add the drained spaghetti and parsley, tossing to coat.

Plate and sprinkle with Parmesan cheese, serving hot.