With a spoon, scoop out the onion and garlic and place in large stock pot. Remove the flesh or "meat" from each half. Run your spoon between the skin and the flesh and place into the pot. Discard or compost the flesh.
Over medium high heat add the chicken stock, bay leaves, jalapeno and Serrano peppers to the pot. Bring to a boil. Once boiling let cook for 30 minutes.
At 30 minutes, turn heat down and remove bay leaves and peppers. Squeeze approximately 1 tablespoon of juice from the peppers and return to the pot. (you may add as much juice as you like, this will control the overall heat of the dish). Stir to combine the pepper juice and let simmer for an additional 30 minutes.
At 30 minutes, remove from heat. With an immersion blender, blend ingredients until smooth. If you do not have an immersion blender, work in small batches once the soup has cooled in a regular blender.
Add in the beef stock, stir to combine and let simmer over medium heat for another 30 minutes.
Serve with sour cream, Sriracha, parsley or tomato.