Bring a large pot of salted water to a rolling boil and cook the pasta until just al dente, about 8-10 minutes. Drain and set aside, saving a cup of pasta water.
While the pasta cooks, drain your soaked cashews and add them to a blender along with plant-based milk, nutritional yeast, lemon juice, minced garlic, nutmeg, and a pinch of salt. Blend until completely smooth and creamy, scraping down the sides as needed.
Heat olive oil in a sauté pan over medium heat until shimmering. Add the minced garlic and sauté for about 30 seconds, or until fragrant and just starting to turn golden.
Pour the cashew cream into the sauté pan with garlic. Warm gently over low heat, stirring constantly, until heated through and slightly thickened, about 3-4 minutes. If the sauce thickens too much, stir in a splash of reserved pasta water to loosen it to a silky consistency.
Add the cooked pasta to the sauce, tossing gently to coat every strand evenly. Adjust consistency with more pasta water if needed, until the sauce is velvety and clings beautifully.
Taste and adjust the seasoning with additional salt or lemon juice if desired. Serve immediately, garnished with fresh herbs or a drizzle of olive oil for extra flavor.