Cream fat and 200 g sugar with the whisk of the hand mixer. Stir in the eggs one after the other. Mix flour and baking powder. Stir yoghurt, 3 tablespoons lemon juice, lemon peel and flour mixture briefly into the fat cream.
Grease a box form (25 cm long; 1.5 litres capacity) and dust with flour. Add the dough and smooth it down. In a preheated oven (electric cooker: 175 °C/ circulating air: 150 °C/ gas: level 2) 55
Let the cake cool down for about 10 minutes. Put 50 g sugar, 120 ml water, 3 tablespoons lemon juice and lemon zests in a pot. Bring to the boil, simmer over high heat for about 4 minutes. Turn the cake out of the tin, carefully turn it over again.
Drizzle the hot syrup over the cake, spreading the zests over the cake. Let it cool down.