4 Green onions, sliced into thick rounds
1 cup Sherry vinegar
3 stems Rosemary
2 Cups Olive oil
Salt and pepper, to taste
1. Marinate the onions in the sherry vinegar, rosemary and half the olive oil overnight (or minimum 4-6 hours). Season with salt and grill until they become black and soft, reserving the marinade.
2. Place the cooked onions back into the marinade and allow to sit another hour or so to make sure they are permeated with the vinegar and oil.
3. Remove onions and roughly chop and; place back into the vinegar mixture. Whisk the rest of the oil into the onion-vinegar mixture and adjust seasoning with salt. The mixture should be thick, but have a little viscosity to it.