In a medium skillet, break down chorizo and fry until cooked; add oil as necessary. Transfer the chorizo to a bowl and set aside.
In the same pan you cooked the chorizo, add the onion and garlic and sauté until soft.
Add the chorizo, tomatoes, balsamic vinegar, sugar, cayenne and salt to the skillet; simmer on low 10 minutes or until the flavors come together and the mixture thickens slightly.
Transfer the jam to a blender (or, using an immersion blender), blend until smooth. Transfer back to skillet and simmer an additional 5 minutes.
Transfer the mixture to sterilized jars. Top with canning lid and ring; allow to cool; transfer jars to the refrigerator.
Enjoy with eggs, on toast, as an addition to your cheeseboard, or as a condiment on your hamburger. Use within 7-10 days.