Peel the cassava completely, removing both the thick brown skin and the pinkish layer underneath. Wash thoroughly.
Place the peeled cassava in a cooking pot.
Add enough water until the cassava is fully submerged.
Bring to a boil over high heat.
Once boiling, reduce to low heat and simmer for about 10–15 minutes or until fork tender.
Drain the cassava and allow it to cool just enough to handle comfortably.
Remove the thick woody string found in the center of each cassava piece.
Mash the cassava using a fork first.
Continue mashing using your hands while wearing food-safe gloves until smooth.
Add the condensed milk, butter, sugar, salt.
Mix and mash thoroughly until everything is evenly combined.
Transfer the mixture into a 12 × 9-inch serving plate.
Flatten and shape into an even rectangle.
Brush the top generously with softened butter.
Use a fork to create decorative lines on top.
Sprinkle generously with grated cheddar cheese.
Slice into serving portions.
Serve and enjoy!