Brown the chorizo in a skillet over medium heat until cooked through, breaking it into small pieces as it cooks. Drain excess fat and transfer the meat to the slow cooker.
Add the diced onion, bell peppers, garlic, black beans, diced tomatoes with green chilies, cumin, chili powder, and salt to the slow cooker. Stir everything together until well combined.
Cover and cook on low for 6 hours or on high for 3 hours until the vegetables are tender.
In a bowl, whisk the eggs until smooth. Pour them over the cooked mixture in the slow cooker and stir gently to combine.
Sprinkle the shredded cheddar cheese on top, cover again, and cook on high for 20 to 30 minutes until the eggs are just set.
Spoon the mixture into bowls and add cilantro, avocado, and salsa before serving.