In a large deep skillet, saute' your garlic, onions, salt, pepper in the olive oil. I use popcorn salt for a buttery rich taste.
Cook on medium high stirring constantly so the garlic does not burn. When the garlic is toasty, add in the green beans and balsamic vinegar. Cook until almost to your liking (crisp-tender). Stir frequently.
Add 1/4 to 1/3 cup of water. Put a lid on and turn off the heat but don't remove the pan from the burner. just let it sit there for 4-5 minutes.
Taste to see if it needs more seasoning and add a little more of the balsamic vinegar.