Cook the pasta: Bring a large pot of water to a boil and salt it. Cook the pasta making sure it's not quite al dente (so about 1 minute less than the cooking time, because you'll be combining in the skillet with the sauce and heating together and it will cook a little more).
While the pasta is cooking, prep the coconut milk/mushroom sauce.
In a small bowl, whisk together the cornstarch with the water. If needed, strain it to get out all the clumps. Set aside.
Cook the sauce: Heat 2 tablespoons olive oil in a large skillet over medium heat. Add shallots (or onion) and season with salt and pepper. Cook, stirring occasionally, until the shallots have become translucent and have totally softened, 5 to 8 minutes. Add in the mushrooms and stir for a minute (they’ll cook very fast!).
Add the wine (broth if you’re not using wine), coconut aminos (or soy sauce, if using), coconut milk, cornstarch mixture, nutritional yeast, garlic powder. Taste the sauce and add some more salt and pepper to taste (or spice it up, if you like) and simmer (about 3-5 minutes). Stir to combine.
Drain the pasta and combine: When pasta is cooked reserve some of the pasta water (1/2 cup is good), drain well and immediately add the pasta to the pan with the coconut sauce. On medium heat, give it a nice stir to combine it all together. If it’s too thick, loosen it with a little bit of the reserved pasta water and stir it all together. Add in the arugula and stir to combine (the arugula will wilt very quickly).
Serve: Plate up your pasta and serve with a sprinkle of nutritional yeast or some vegan parmesan. Enjoy!