Preheat a cast iron or stainless steel skillet on medium heat with your oil of choice.
Dice onions into pieces no bigger than a half inch square.
When the skillet is preheated, add the onions and reduce the heat to medium low to caramelize. Gently sauté the onions until translucent and light brown. Be sure to stir the onions occasionally. See post for a reference picture for the light brown color.
When the onions are caramelized, add in the garlic and cook until fragrant. After the garlic has become fragrant, remove from the heat and cool for 5-10 minutes.
Mix all ingredients in a medium bowl until everything is well incorporated.
Transfer to an airtight container and place in the refrigerator to let the flavors marinate for at least an hour.
Serve with any arrangement of vegetables, crackers or chips.