In a small saucepan, over medium heat, add the milk and bay leaf and bring to a simmer, about 5 minutes. Remove milk mixture from heat and allow to cool slightly. Do not remove the bay leaf at this time.
Remove the bay leaf from the milk mixture. Slowly add the milk to the onion mixture, stirring to combine. Continue to cook, stirring often, until the milk-onion mixture has thickened, about 5 minutes.
Pour the milk-onion mixture into a strong blender (such as the Vitamix). Add the cilantro and blend until smooth.
Pour the puree back into the pan. Over medium heat, add the chicken broth and pepper and stir to combine. Simmer the soup for another 10 minutes.
Divide the soup evenly among 3 bowls. Serve with tortilla chips if desired.
Recipe by The Little Chef at http://littlechefblog.com/cilantro-soup/