Cook the Vegetables: Boil the colocasia pieces for 20-25 minutes until fork-tender.
Boil the quartered potatoes for 20-30 minutes until tender.
Boil the peeled and halved plantain for 25-30 minutes until tender. For best results, drain all vegetables well and let them steam dry in a colander or on a clean kitchen towel to remove excess moisture.
Prepare the Mixture: Once cool enough to handle, peel the cooked colocasia.
In a large mixing bowl, mash the colocasia and potatoes.
Grate the cooked plantain using the coarse holes of a grater and add it to the bowl.
Combine and Season: Add the cracked black pepper, minced chilies, salt, optional arrowroot powder, and fresh coriander to the vegetable mixture.
Knead everything together until well combined.
Shape the Croquettes: Lightly oil your hands.
Divide the mixture into 14 even portions.
Roll and press each portion into a smooth log about 2 inches / 5 cm long, or into a doughnut shape about 2 inches / 5 cm in diameter.
Place them on a sheet of waxed paper.
Heat the Oil: In a deep-fryer or heavy-bottomed pan, heat ghee or oil to a depth of at least 1. 5 inches / 4 cm. Use a thermometer to ensure the oil reaches and maintains a temperature of 370°F / 190°C.
Fry to Perfection: Carefully add half of the croquettes to the hot oil, ensuring not to overcrowd the pan.
Fry until they are a rich, golden brown.
Remove with a slotted spoon and let them drain on paper towels.
Serve Immediately: Serve the croquettes piping hot, ideally in a napkin-lined basket. For an extra touch of flavor, top each one with a small pat of Mint-Lime Butter and let it melt over the top.
After boiling the potatoes and colocasia, let them steam dry completely. Excess moisture is the enemy of a crispy croquette.
