Prepare a pot of salted water to cook the pasta.
In a large skillet heat up olive oil on high heat. Then reduce heat and add the sliced mushrooms, chopped leeks and chopped zucchini. Sauté for 7-8 minutes, stirring often until softened.
Add minced garlic, salt and pepper, continue cooking for 1-2 minutes.
Then add the broth, half and half, Dijon mustard, a sprinkle of salt and pepper. Stir everything and bring to a low-boil. Then cook until sauce had thickened, about 8-9 minutes.
Follow pasta instruction on package, drain pasta once al dente and set aside. Make sure to reserve at least ¼ cup of pasta water.
Add the reserved pasta water and parmesan and continue cooking for 3-4 minutes.
Add the pasta and the lemon juice to the skillet , stir everything well. Adjust salt and pepper. Portion pasta in plates or bowls, sprinkle with fresh chopped parsley and more parmesan, serve and enjoy!