Put the potatoes in a pan of cold water and cook them until just tender. Drain, rinse under cold water and drain again. Let them cool.
Put the eggs in a small pan of cold water. Bring to the boil, cover the pan, turn off the heat. After 6 minutes rinse the eggs under cold water, then rest them in a bowl of cold water.
Cut the potatoes into long slices. If they are not organic, peel them first.
Remove the egg shells, then cut the egg into slices.
Thinly slice the onion and celery. Finely chop the garlic and carrot.
Heat the oil in a frying pan and sauté the onion, celery and carrot for 5 minutes. Add the garlic, herbs and balsamic vinegar and stir for a minute.
Add the chopped tomatoes. Season with salt and pepper.
Cook for 10 minutes, until you get a nice, thick sauce.
Add the fresh herbs, then blitz the sauce, using a stick blender, until you get a coarse finish. Set aside.
Preheat the oven to 180°C.
Grease one large or two medium deep dishes with oil, then add a layer of potatoes, the eggs, then mixed fish, then cover with the sauce. You can add some cheese if you like.
Repeat the layers, leaving enough potatoes to be the top layer.
Cover the dish with potato slices, then brush them with olive oil and season with salt.
Alternatively scatter some cheese over the potatoes.
Bake for 25-30 minutes, until the cheese has melted or the potatoes are golden.
Serve warm.