1. In a kettle or pot, bring 3 cups of water to a boil. In a large frying pan, melt the margarine. Whisk in flour until it is all mixed together and bubbling. You can add more margarine if needed. Slowly add the boiling water and whisk in as you go, paying attention to the thickness. If you have ever made gravy, it should look about the same.
3. Whisk in the salt, garlic powder, and turmeric. Keep whisking in water until it has the consistency of a nacho cheese sauce. Note that I didn't use all 3 cups of the water and just kept adding it until reaching the proper consistency.
4. Whisk in the nutritional yeast in small amounts. Let boil for about 2 minutes and then toss with pasta. Yummy!
Source of recipe: Playing around in the kitchen, looking over about six recipes!