1. Bring a large pot of salted water to a boil and cook the pasta according to package instructions until al dente. Drain and set aside, reserving about 1/2 cup of pasta water.
2. In a large skillet, heat the olive oil over medium heat. Add the sliced mushrooms and cook, stirring occasionally, until they are golden brown and have released their juices, about 8-10 minutes.
3. Add the minced garlic to the mushrooms and cook for another 1-2 minutes until fragrant. Be careful not to burn the garlic, as it can become bitter.
4. Stir in the heavy cream and bring to a simmer. Let it cook for about 3 minutes until slightly thickened.
5. Add the cooked pasta to the skillet, tossing it with the mushroom sauce. If the sauce is too thick, add a little of the reserved pasta water to reach your desired consistency.
6. Stir in the Parmesan cheese, salt, pepper, and red pepper flakes (if using). Toss until the pasta is well coated and everything is heated through.
7. Remove from heat and sprinkle with fresh parsley before serving.

Remember, cooking is an art, not a science. Feel free to adjust the seasoning to your taste, just as I learned to do when experimenting with flavors in my kitchen.