Now, peel and dice the onion and finely chop the garlic. Add 1 tsp of olive oil to the saucepan over a medium heat, then add the onion and sauté for two minutes or until translucent. Next add in the chopped garlic and continue to sauté for another minute or until slightly golden and aromatic.
Next, scrape out the onion and garlic into a blender or bullet blender cup. Place in the mustard, nutmeg, turmeric, nutritional yeast, lemon juice, water then cube and add in the silken tofu.
Blitz this mixture on high until smooth and creamy, yet it should still be pourable. Place your cheesy sauce to one side.
Fill the same saucepan with water and bring it to the boil, then add in your pasta and cook according to the package instructions (this is usually around 6 minutes).
Next, reserving some of the pasta water, drain your pasta and place it back into the saucepan along with the cheesy sauce. Bring this to a low heat and cover with a lid to gently simmer and heat through thoroughly for 2 minutes. If your sauce becomes too thick, thin it out with your reserved pasta water. (The sauce will alo thicken forther once cooled.)
Finely chop the parsley and add it to the mac' n' cheese along with salt and pepper to taste; incorporate everything evenly.
Plate up your delicious American cuisine over a bed of spinach and garnish with extra parsley and roasted garlic mushrooms. Enjoy!