Place the onion, red bell pepper, garlic, scallions, cumin, achiote and 3 tablespoons of water in the blender.
Place the chicken broth or water in a large pot, add the onion mixture, chicken pieces and bring to a boil. Reduce the heat to medium and cook for 40 minutes.
Add the chopped potatoes, yuca, plantains and pumpkin and cook for 30 minutes more, stirring occasionally.
Add the carrots and cook for 10 minutes more. Add the chopped cilantro and serve with avocado slices and hot sauce or aji.