basil, basal

Basil or basil means the culinary herb, related to mint--
Add a teaspoon of chopped fresh basil, and bring the sauce to a boil.
He keeps a pot of basil growing in the kitchen window.

Basal or basal ( rhymes or nearly rhymes with basil ) describes something related to a bottom layer or minimum level, or to a foundation--
The doctor prescribed a basal level of a new drug; the dose might be increased if necessary.
The basal leaves will emerge from the root in a few weeks.
The basal reader is about the right level for this class.

Now that you know that, you can say--
"The basal amount of basil is about a teaspoon to a quart of sauce."

Note--"Basil" ( always capitalized, nearly rhymes with castle ) is a male's given name--
His name is Basil, but everyone calls him Tex.