Meanwhile, wash cashews in a colander under very hot water. Place drained cashews, 1 1/2 cups water, seasonings (except parsley), lemon juice, and tahini in blender. Blend on high-speed until smooth. Mixture should be very smooth with no graininess.
Add cornstarch or arrowroot and blend until well mixed. Add olive oil and blend until well mixed.
Pour mixture into a saucepan. Rinse blender out with remaining 2 cups water and pour into saucepan.
Bring mixture to boil over medium to medium-high heat, stirring constantly. Using a heat-proof spatula against the bottom of the pan will help prevent mixture from scorching.When mixture is thick and bubbly, remove from heat. Stir in parsley.
Drain pasta. Combine pasta and sauce and toss until well coated.
Season to taste. Serve hot.
Notes
A heat-proof spatula is a handy tool for stirring the sauce while it is cooking.* * * This recipe for Fettuccine Alfredo is … gluten-free, plant based, sugar-free, high in fiber, dairy free, egg-free, vegetarian, vegan, and made from real, whole foods.