Combine ingredients: Whisk together eggs, sugar and vanilla sugar until dissolved. Then stir in oil and lemon zest. Now gently fold in flour and baking powder until you have a smooth dough. Now add milk, melted (but not too hot) butter and poppy seeds, and whisk into the dough until fully combined.
3 eggs, 140 g sugar (⅔ cup), 1 sachet vanilla sugar (15g or 1 tbsp); or 1 tsp vanilla extract, 15 g vegetable oil, zest from 1 lemon, 175 g flour (1.4 cups), 1 sachet baking powder (8g or 3 flat tsp), 150 g melted butter (1 ¼ sticks or 10 tbsp) (Plus some more to butter the mold), 50 ml milk (1.7 oz), Optional: 1 tsp poppy seeds