In a large pot, bring water to a boil (about half filled), then add the tomatoes whole. Allow them to sit in the boiling water for 30 seconds, then remove and immediately peel the skin off the tomatoes.
Quarter the tomatoes, then place them, along with the other ingredients in a juice blender (or bowl, if no juice blender and are using a hand blender).
Blend the ingredients into juice form, then pour into cups and enjoy.
Instead of cayenne, you can use a fresh jalapeño pepper. Simply remove the seeds and stem, then roughly chop the pepper and add the chili during the blending process. Use half a pepper to start, then ramp up from there.