1. Prepare the Vegetables: Peel the cassava, sweet potatoes, yam, eddoes, and plantains. Cut them into medium-sized pieces so they cook evenly.
2. Prepare the Cassava: Remove the tough central fibre from the cassava. Use properly prepared food-grade cassava and cook it thoroughly before eating.
3. Boil the Water: Place the vegetables in a large pot and add enough water to cover them. Add salt.
4. Cook the Firmer Vegetables: Bring the water to a boil. Add cassava, yam, and eddoes first, then reduce the heat and simmer for about 10–15 minutes.
5. Add the Remaining Vegetables: Add sweet potatoes and green plantains. Continue cooking until all the vegetables are completely tender.
6. Check for Doneness: Pierce the vegetables with a fork. They should be soft but still hold their shape. Drain the cooking water carefully.
7. Season and Serve: Add butter and black pepper if desired. Gently toss the vegetables and serve warm with fish, meat, or a traditional Guyanese stew.