Tarragon is not a herb that you can add wherever you want. You have to find a recipe suggesting it because its taste is very unique. Of course you can always experiment and you will discover how versatile it can be with its strong sweet taste.
It pairs well with: sauces, meat, chicken, dishes with egg, fish, and vegetables. It is used along with anise in soups that have tomato as main ingredient or in tomato sauces for pasta.
The low shrub which is native to Asia is actually a member of the lettuce family. In its dried from, its taste is light and sweet. Tarragon is one of the four main herbs of the French cuisine and pairs really well with chicken, fish, and dishes with egg. It is also the main ingredient of the aromatic Béarnaise sauce.