How to Make It
In a small saucepan combine the vinegar, tequila, sugar and garlic. Over medium heat, bring to a boil and simmer for a few minutes.
In a medium bowl, place the onions, pour in the mixture, add the thyme and season with salt and pepper to taste. Let sit at room temperature for at least 2 hours. Drain the onions.
Pour water over bread to cover, squeeze out the water and place bread in the bowl of a food processor and puree until smooth. (If too thick, add a little ice water to thin out.)
Strain through a fine sieve and season with salt and pepper to taste.
Cover and refrigerate at least 2 hours. Divide among six bowls and garnish with the pickled onions and cilantro.