Set a pot of water and over high heat. Once at a boil, add cashews and salt and boil for 10 minutes. Next, drain cashews from the water and keep leftover cashew water.
In a blender, add cashews, nutritional yeast, smoked paprika, tomato paste, garlic powder, fresh lemon juice, salt, dijon mustard, and 1.5 cups of the leftover cashew water. If you want the sauce to be creamier and buttery, add vegan butter (optional). Blend until smooth.
Prepare the pasta according to the package’s instructions. Stir together cheese sauce to the pasta. Add additional salt to taste.
To store: This recipe is best served right away. Like traditional mac and cheese, this recipe can dry up quickly. However, it may be stored in the refrigerator for up to 4 days in an airtight, sealed container. To reheat: To reheat, transfer the mac and cheese to a pot. Warm over low heat and stir in a little bit of water or non-dairy milk to loosen up the sauce. Heat until warm all the way through.