Peel and wash potatoes. Add to pot of boiling water. Boil until potatoes are soft through, about 20 minutes.
Remove from water. Add to a large bowl and mash until light and fluffy.
Heat oil in a pan or skillet over medium-low heat. Add the green chilies and curry leaves and heat for 3-5 minutes.
Add onion, garlic, and ginger. Sauté until onions are aromatic and start to brown, about 5 minutes.
Increase heat to medium-high. Add chopped salmon and cod fillets, and cook for 3-5 minutes, stirring occasionally.
Remove from heat and leave to cool
In a large bowl, add the fish mixture, mashed potatoes, and garam masala. Combine well. Add salt to taste.
Form 20-30 small bowls from the cutlet mixture, pressing each one lightly to form round patties.
Crack and whisk the egg in a small bowl. Pour the breadcrumbs into another bowl.
Dip each patty into the egg mixture, covering evenly, and then roll in breadcrumbs. Place each coated patty on a wire rack or baking tray.
Heat cooking oil in a skillet or pan over medium-high heat. In small batches, place the cutlets in the oil and fry until golden, flipping halfway through.
When each cutlet is done, remove from the pan and place a wire rack to cool and drain
Serve immediately and enjoy