boil down vs cooking

boil down is not a noun while cooking is a noun.

Word	Noun	Adjective	Verb	Adverb
boil down	No	No	Yes	No
cooking	Yes	No	No	No

boil down (noun)	cooking (noun)
	the act of preparing something (as food) by the application of heat

boil down (verb)	cooking (verb)
cook until very little liquid is left
be cooked until very little liquid is left
be the essential element