Marinate beef with crushed garlic, pisco, pepper and cumin for at least one hour or overnight.
Drain beef (discard marinade) and brown in a heavy-bottomed pot with one tablespoon of ghee. Reserve.
Lower heat, and in the same pot melt another tablespoon of ghee. Cook onion, minced garlic and chilli until very soft, approximately 10 minutes.
While the aderezo is cooking, blend coriander with kombucha.
Add pumpkin to the pot, cook for a minute, stirring often.
Add meat, blended coriander, and stock to the pot. Season with salt and pepper and simmer covered until soft (1.5 to 2 hours).
While you wait, boil cassava in water until soft. Drain and reserve.
Add orange juice. Let reduce with the lid off if there's too much liquid for your liking.
Fry cassava in butter and sprinkle with salt. Serve.