Bring a large pot of salted water to a rolling boil, then add your pasta and cook until al dente, about 8-10 minutes. Drain and set aside, reserving a splash of pasta water.
While the pasta cooks, heat a large frying pan over medium-high heat and add olive oil. Once shimmering, add the sliced cremini mushrooms in an even layer. Let them cook undisturbed for about 2-3 minutes until edges turn golden and crispy.
Stir the mushrooms and cook for another 3-4 minutes until they release their juices and become tender, with a rich, caramelized aroma filling the kitchen.
Add the minced garlic to the pan and cook for about 30 seconds until fragrant, making sure it doesn't burn. Then, splash in the soy sauce, stirring quickly to coat the mushrooms evenly.
Pour in the vegetable broth or reserved pasta water to deglaze the pan, scraping up any browned bits from the bottom. Stir in the lemon zest and nutritional yeast, allowing the mixture to simmer gently and thicken slightly, about 2 minutes.
Add the drained pasta to the pan, tossing well to coat every strand with the mushroom sauce. If the sauce seems too thick, add a splash of the reserved pasta water to loosen it up and create a glossy finish.
Cook everything together for another minute, allowing the flavors to meld and the pasta to soak up the sauce. Taste and adjust seasoning if needed—perhaps a little more soy or lemon zest for brightness.
Serve immediately on warm plates, garnished with extra lemon zest or fresh herbs if desired. Enjoy the rich, earthy aroma and the velvety, umami-packed texture of this hearty vegan mushroom pasta.
