Fry a large, flat skate on the stove. As it cooks, the pink-tinged flesh turns white with a firm texture. Once cooked, the meat comes away easily from its supportive bony framework with a fork.
To make Tuna Fish Cakes, start by draining the canned tuna.
While the rice is cooking, prepare the eel by grilling or frying it.
Put the tomato paste, olives, and butter into a blender or food processor and whizz until smooth.
Put the oats in the blender or food processor, slightly broken up.
Coat the fillets with the butter mixture while grilling.
Heat a large skillet over medium-high heat and add the fish cakes.
To make the mashed potatoes, pour over the olive oil into the bowl of cooked potatoes. Mash the potatoes until they are well blended and lump-free. Season with salt and pepper.
Dip in the flour and coat each fishcake. Dip in the egg and then coat with crumbs. Repeat this process until you have 24 fishcakes. Chill the fish cakes for one hour.