'indispensable ingredient' is a correct and usable phrase in written English.
You can use it to refer to something that is essential or necessary for something else to work, or for something to be complete. For example, "Love is an indispensable ingredient for a successful marriage."
The celebrity factor is an indispensable ingredient - a touch of glamour, of real magic.
THE indispensable ingredient in great whiskey is time: years of aging and mellowing in casks.
Teff is the indispensable ingredient in injera, the disc-shaped bread that Ethiopians use to scoop up food.
Water is considered an indispensable ingredient of life, and its presence on Mars is of increasing interest to scientists who suspect that life once existed on the planet.
In lovers' songs, military marches, weddings and funerals -- every occasion where a degree of emotion needs to be evoked -- music is an indispensable ingredient.
For this odd, mysterious play to spring to theatrical life, the one indispensable ingredient is probably an impassioned performance in the role of Solness.
These salted Ortiz anchovies from Spain are indispensable ingredients in the River Café larder.
In Puerto Rico, the indispensable ingredients are cilantro and recao, a strong-smelling herb with long, spiky leaves found there in backyards.
The irony is now complete: where once sincerity and personal revelation were considered the indispensable ingredients for rock's ambitions, disposing of them has become the first step toward realizing fully mature work.
Inventions and technological breakthroughsand their subsequent application to the providing of better or new services and productsare the indispensable ingredients for economic progress.
With rapid advancement of Cloud computing and networking technologies, a wide spectrum of Cloud services have been developed by various providers and utilized by numerous organizations as indispensable ingredients of their information systems.
