Bring a large pot of salted water to a boil. Cook the fettuccine noodles until perfectly al dente. Reserve 1/2 cup (120ml) of the starchy pasta water, then drain the noodles.

In a high-speed blender, combine the soaked and drained raw cashews, vegetable broth, minced garlic, nutritional yeast, fresh lemon juice, and 1/2 tsp of coarse kosher salt. Blend for 60-90 seconds until a thick, glossy, creamy pale-ivory sauce forms. Use a splash of reserved pasta water if it needs thinning.

Pat the chicken breasts dry and rub evenly with olive oil, the remaining 1/2 tsp salt, and garlic powder. Heat a large skillet over medium-high heat and sear the chicken for 6-7 minutes per side until a golden-brown, slightly charred crust develops. Let it rest for 5 minutes.

Return the drained fettuccine to the pot over low heat. Pour the cashew Alfredo sauce over the noodles, tossing vigorously. Add splashes of reserved pasta water until the noodles are thoroughly coated and glossy.

Slice the rested chicken into thick, overlapping pieces. Transfer the pasta to a shallow white ceramic pasta bowl, top with the chicken, and garnish generously with finely chopped fresh green parsley and coarse cracked black pepper.