Bring a large pot of salted water to a boil. Add your pasta and cook until al dente, about 8-10 minutes. Drain and set aside.
While the pasta cooks, heat olive oil in a large skillet over medium heat. Once shimmering, add the sliced mushrooms and cook, stirring occasionally, until they turn golden brown and fragrant, about 8 minutes.
Push the mushrooms to one side of the skillet, then add the finely chopped onion and minced garlic to the empty space. Sauté until translucent and fragrant, about 5 minutes.
Sprinkle the smoked paprika over the mushroom mixture and stir well to toast the spice for about 1 minute, releasing a warm, smoky aroma.
Pour in the vegetable broth, scraping any browned bits from the bottom of the skillet. Bring the mixture to a gentle simmer and cook until slightly reduced, about 5 minutes.
Stir in the vegan sour cream, mixing until the sauce becomes velvety and smooth. Let it cook gently for another 2 minutes, allowing the flavors to meld.
Add the cooked pasta directly into the skillet, tossing to coat the noodles evenly with the mushroom sauce. If needed, loosen the sauce with a splash of reserved pasta water.
Garnish with chopped fresh parsley and give everything a gentle toss. Serve immediately while hot and fragrant, with the earthy aroma of mushrooms filling the air.
