Heat oven to 350°. Cook pasta noodles according to package directions. Drain, rinse and place into a 9x11” baking dish.
Place all the ingredients into a high-powered blender, the drained, soaked cashews along with the non-dairy milk roasted peppers, nutritional yeast, lemon, and mustard along with the spices, and arrowroot.
Pour blended sauce into a saucepan over medium heat. Whisk constantly until the sauce thickens.
Pour “cheese” sauce over noodles and if you’re adding any additional vegetables like peas or broccoli, add those in and stir all to combine.
To make the parmesan "cheese," put all of the ingredients in a high powered blender and blend until crumbly. Sprinkle on top of your mac and cheese or use bread crumbs.
Cook for 25 minutes or until hot and bubbly and the edges start to brown.