I tried the original posters version and then tweaked that, as it was too sweet in comparison to the real thing. As I tweak it more, I will come and update the recipe for you. But here it is thus far.
1 1/4 c. nutritional yeast
2/3 c. water
2 T soy sauce
1 T red wine vinegar
2 t. Dijon mustard
1 medium garlic clove, crushed
1/2 c. extra virgin olive oil (or 1/4 c. EVOO and 1/4 c. flavorless oil, like canola or sunflower)
Mix nutritional yeast and water together in a bowl or measuring cup. Add to blender. Add the soy sauce, red wine vinegar, Dijon mustard and crushed garlic and blend well. Slowly add the oil and blend until well mixed.