Knead butter, flour, 75 g sugar and 1 packet of vanilla sugar with the dough hooks of the hand mixer to form crumbles. Put in a cool place. Place the eggs, 125 g sugar, 1 packet of vanillin sugar and salt in a mixing bowl. Whisk with the whisk of the hand mixer until white-creamy. Mix the quark and pudding powder. Carefully fold the egg-sugar mixture into the quark mixture.
Place a paper sleeve in each trough of the muffin tray (12 pieces). Pour in the quark mixture. Spread crumbles over it. Bake in the preheated oven (electric cooker: 200 °C/ convection oven: 175 °C/ gas: level 3) for about 30 minutes. Let the muffins cool down on a cake rack. Stir icing sugar and lemon juice until smooth and sprinkle over the muffins