Informative "Risk" chapter. Long suspected something like that but never quite found a way to put it into words.
Might also want to put the "Starting Quality" calculation into the guide as well:

NQ Ingredient => 0 base
+1 Ingredient => +100 base
+2 Ingredient => +200 base
+3 Ingredient => +300 base
Adjusted Base Quality = Sum(IngredientBaseQuality)/NumberOfIngredients
Actual Base Quality = Adjusted Base Quality + a small positive random value (~1 to 20ish)

E.g. So a 3 ingredient recipe where you use 1 NQ, +1 and +3 ingredient will give you around 133 quality.