Peel and cut the Mandioquinha into roughly equal chunks so they cook evenly.
Heat a large pot over medium heat and add Olive Oil and Unsalted Butter until the butter melts and begins to foam.
Add a diced Onion and minced Garlic to the pot and sauté until the onion is soft and translucent and the garlic is fragrant, about 4–5 minutes.
Add the prepared mandioquinha to the pot, stir to coat with the aromatics, then season with Salt and freshly ground Black Pepper.
Pour in enough Chicken Stock to just cover the vegetables, bring to a gentle boil, then reduce heat and simmer until the mandioquinha is very tender, about 15–20 minutes.
Use an immersion blender to purée the soup directly in the pot until smooth, or carefully transfer in batches to a countertop blender and blend until silky.
Return the blended soup to low heat and stir in the Creme De Leite to warm through; taste and adjust seasoning with more Salt and Black Pepper if needed.
Ladle the soup into bowls and finish with a sprinkle of chopped Cheiro-Verde for color and fresh herb flavor. Serve immediately.
