Peel Garlic bulbs and cloves. You can soak cloves in Hot water to make it easier to get the papery shell off.
Peel Onions and cut each into 4 quarters.
Use a food processor or blender. Place the cloves and the onions into the device, pulse to rough chop to your desired consistency. I like it chunkier, but you can even pulse until it is a puree.
Heat 2 Tablespoons of olive oil in a 12 inch skillet over medium high heat. Add garlic and onions, sauté’ until golden brown.
Add Balsamic Vinegar and Fish Sauce to the pan, stir well to deglaze the bits that might be stuck to your pan. Simmer for 4-5 minutes. When the mixture has reduce in volume, add the brown sugar and the chili garlic sauce. ( I tend to use a 1/2 cup of chili garlic sauce for mild heat, I will add more if I want it to be medium to hot spicy.)Stir mixture frequently as it cooks, to dissolve the sugar. The paste is done when it is shiny and jam like in consistency.
You can store your paste in a glass jar in the refrigerator for up to 2 months.
See how I use the paste by looking at my other recopies with the term zippy in the title.