How to make
Remove visible bones from fish fillets, rinse it under running water water very briefly and then dry it well.
Peel and cut the potatoes into thin slices, arrange them in a baking pan and sprinkle them with olive oil, black pepper and salt.
Place the perch fillets on top of the potatoes, drizzle them with a little olive oil as well, lightly sprinkle some salt, pour the white vermouth, spread the mayonnaise and finally sprinkle a little tarragon.
Put the baking pan in an oven heated to 390°F (200°C) for 30-35 minutes, if the fillets are at least 0.8″ (2 cm) thick.
If they are thin, from smaller fish, then proceed in another way - first bake only the potatoes for about 15 minutes, then add the fish and bake it for 20-25, or until the mayonnaise on top starts to aquire a light golden brown color.
Enjoy your meal!