Preheat oven to 350°
Salt the pasta water with 2 tbsp sea salt and bring to a boil. Cook as directed on the package. For best results, drain the pasta 2 minutes less than the recommended time.
Steam 1 cup cauliflower until it’s tender, approximately 5 minutes. Let cool.
Drain and rinse the cashews and put in a powerful blender or food processor. Add the 1 cup steamed cauliflower, ½ cup plus 2 tbsp nutritional yeast, 3 tbsp vegan butter, 1 tbsp lemon juice, ¼ tsp cayenne pepper, ½ tsp paprika, ¼ tsp garlic powder, ¼ tsp onion powder, 1 tsp sea salt, and ½ cup plant milk (add more if needeand blend until the cheese sauce is smooth and creamy. Scrape the sides once or twice while blending to ensure that there are no solid pieces of nuts.
Taste the cheese sauce and add more salt, the black pepper, and more cayenne if you want a spicier mac and cheese, blend for 20 seconds.
When the pasta is al dente (cook for 2 minutes less than the package recommenddrain the water and place in a medium lasagna pan or a shallow baking dish. Pour the cheese mixture on top and stir it well to coat all of the pasta. Broil for 2 to 3 minutes, or until it begins to brown on top.
Sprinkle with coconut bacon if desired.