Line recesses of the muffin tray with paper baking cups. Preheat the oven (electric cooker: 180 °C/circulating air: 160 °C/gas: see manufacturer). Wash the lemon, dab dry and grate half of the peel.
Whisk butter, sugar, vanilla sugar, lemon zest and 1 pinch of salt with the whisks of the mixer until thick and creamy.
Stir in the eggs. Mix flour and baking powder. Stir yoghurt briefly into the butter mixture. Spread the dough evenly over the hollows of the muffin tray. Bake in a hot oven for 18-20 minutes. (Not too long!) Take out of the oven and let it cool down.
Cut the vanilla pod in half lengthwise with a kitchen knife. Scratch out the pulp with the back of the knife. Cream vanilla pulp, cream cheese, milk and icing sugar with the whisk of the mixer.
Fill the cream cheese freezing in a piping bag with star-shaped spout. Place 1 marshmallow on each muffin and spray the frosting onto the muffins in a circle. Sprinkle with coconut flakes and refrigerate for at least 30 minutes.