Boil the potatoes in salted water, mash and keep aside.
Use a food processor or finely chop the onion, garlic, ginger and green chillies.
Do the same for the tuna fillet too; do not over process or it goes pasty.
In a large bowl, combine the tuna, onion mixture, mashed potatoes, spices and coriander leaves; season with salt. Combine well till all the ingredients are blended well.
Form into small croquettes or patties; the choice of shape is entirely yours. Keep aside.
Season the breadcrumbs and beaten eggs with salt and pepper.
Dip each croquette in the egg wash and then roll well with breadcrumbs. Repeat for all others.
Heat enough oil for deep frying in a large deep pan.
Fry the croquettes in small batches till golden brown.
Drain on a kitchen paper and serve warm with any dip of choice. (I served with a mint coriander chutney)
Notes
If you do not want to use all the tuna mixture at a time, then you can freeze the remaining for later use in an airtight container. You can also freeze after rolled in breadcrumbs but make sure you do not crowd the container.