Peel the cassava root thoroughly, removing all brown skin and the fibrous inner core. Cut into chunks and boil in salted water for 20-25 minutes until completely tender when pierced with a fork. Drain well and let cool slightly.

Once cooled enough to handle, grate the cooked cassava using a box grater or process in a food processor until you have a smooth, sticky consistency. Transfer to a large mixing bowl.

Finely chop the onions, mince the garlic cloves, and chop the fresh parsley. Add these to the grated cassava along with the eggs, flour, salt, black pepper, and a pinch of cayenne if using. Mix thoroughly until all ingredients are well incorporated and the mixture holds together.

Heat vegetable oil in a deep pot or dutch oven to 350°F (175°C). The oil should be at least 3 inches deep for proper frying.

Using your hands or a small ice cream scoop, form the cassava mixture into balls about 1.5 inches in diameter. Make sure they are compact and smooth.

Carefully lower 4-5 balls at a time into the hot oil, being careful not to overcrowd the pot. Fry for 4-5 minutes, turning occasionally, until golden brown on all sides.

Remove the fritters with a slotted spoon and drain on paper towels. Season with additional salt while still hot if desired.

Continue frying in batches until all the mixture is used. Serve immediately while hot and crispy.