For the pike-perch fillet with tomato crust on lemon risotto, heat the chicken soup and keep it warm, peel the onion and garlic and cut them into fine cubes. In a wide pot, heat the olive oil and sauté the onion and garlic until translucent. Add the risotto rice and butter and saute for another 3 minutes. Deglaze with wine and let it boil down completely.
Pour in enough soup to just cover the rice. Cook for 20-30 minutes, stirring frequently. Keep adding soup as soon as the rice has almost absorbed the liquid. Grate the zest from the lemons and squeeze the lemon. Season the risotto with lemon juice, zest, salt and pepper.
For the crust, mix the tomatoes well with the remaining ingredients and season with salt and pepper. Lightly salt the fish and sprinkle with a little lemon juice. Spread the tomato crust on the skin side of the fish and let it bake in the oven at 160°C for about 10 minutes.
Finely chop the olives and capers, add anchovies according to taste, pluck the tarragon from the stem and mix with the olive oil. Season with lemon juice, salt and pepper.
Arrange the risotto on a deep plate, place the fish on top and add some of the olive tapenade. Sprinkle with shavings of Parmesan and drizzle with a little olive oil. Serve the pike-perch fillet with tomato crust on lemon risotto immediately.