Heat 1 tablespoon olive oil in a large dutch oven. Add diced onion, carrots and celery and sauté over medium-low heat, stirring often, until softened and lightly golden, about 8 minutes.
Add minced garlic, ground cumin and dried oregano and cook 1 more minute, stirring.
Add chicken broth, bone in chicken breasts and salt. Bring to a gentle boil and cook on low, partially covered for 20 minutes (25 minutes for thighs).
Add sweet potatoes and and cook until veggies are tender, 20-25 minutes more.
Remove the chicken and place in a bowl to cool.
Add kale to the soup and cook for just a few minutes to soften.
Once the chicken is cool enough to handle, shred the meat and add back to the soup.
Season with freshly ground black pepper and more salt, if needed.