Can we preserve garlic and ginger paste?
I've had success freezing it in an ice cube tray. The tray should then be sealed in a bag or box, and you won't want to use it for anything else afterwards - I've never found a way of getting rid of the smell.

If you always use it in larger quantities than one or two ice cubes, by all means freeze it in larger containers, but expect to defrost and use the entire container.