The secret for canned string beans is to simmer with beef bouillon

Personally, when I serve up canned string beans I add in some Worcestershire sauce and powdered garlic before warming them up.

This post recommends simmering beef bouillon with the canned string beans for at least one hour, and if you have time, let it simmer until almost all the broth is evaporated. You can still add your garlic powder or other ingredients, but the secret is in the beef bouillon.