Optional ingrediants

I was thinking about this off and on for the past few days, and what I am suggesting is this;
Optional ingredients for some recipes. We will use a non-existent biscuit as an example. The biscuit would have a set of required ingredients, those being flour, water, and lard (or butter). Also, it has a fourth ingredient, the optional one. This optional ingredient is "any herb." If you leave the herb out, you get the basic biscuit with it's humor values based on which flour you used. If you use the optional though, it gives you the chance to modify the humors in some way both positively and negatively. Say you used flame azalea in the recipe. In this example the flame azalea would further boost, lets say, the yellow humor by a small amount but would decrease one or more of the other humor values of the biscuit. Furthermore, this system could also open up for more imported herbs that would have less negative effects on the food it's used on. People with poison craft could make poisoned foods with specially concocted poisons in the place of an optional ingredient.
Thoughts? Ideas?
Optional ingredients for some recipes. We will use a non-existent biscuit as an example. The biscuit would have a set of required ingredients, those being flour, water, and lard (or butter). Also, it has a fourth ingredient, the optional one. This optional ingredient is "any herb." If you leave the herb out, you get the basic biscuit with it's humor values based on which flour you used. If you use the optional though, it gives you the chance to modify the humors in some way both positively and negatively. Say you used flame azalea in the recipe. In this example the flame azalea would further boost, lets say, the yellow humor by a small amount but would decrease one or more of the other humor values of the biscuit. Furthermore, this system could also open up for more imported herbs that would have less negative effects on the food it's used on. People with poison craft could make poisoned foods with specially concocted poisons in the place of an optional ingredient.
Thoughts? Ideas?