For the dough, whisk 3 egg yolks, 1 tsp salt and curry. Stir in 100 ml water and milk. Sift flour and baking powder on top and stir in well. Let the dough swell for about 30 minutes.
For the tartar sauce, hard-boil 2 eggs. Quench, peel and dice finely. Peel the onions. Finely dice onions and gherkins. Wash and chop the parsley. Mix mayonnaise, sour cream, eggs, gherkins, parsley and half onions. Season with salt, pepper and 1 pinch of sugar.
For the salad, select and wash the spinach. Wash and halve the tomatoes. Mix vinegar, salt, pepper and 1 pinch of sugar. Fold in 2 tablespoons of oil. Mix everything.
For the fried fish, wash the fish, dab dry and cut into approx. 12 pieces. Heat 1 l oil in a large pot to approx. 180 °C. Pull the fish pieces through the batter and deep-fry in portions for 3-4 minutes until golden brown. Drain well. Cut lemon into slices. Arrange everything.