Finely grind the biscuits in a freezer bag with the rolling pin. Melt butter and knead with the cookies. Put them on the bottom of a round pie tin (24 cm Ø) and press them firmly. Squeeze the limes. Mix the milkmaid's milk, quark, eggs and lime juice.
Spread on the biscuit base and bake in the preheated oven (electric range: 175 °C/ gas: level 2) for approx. 30 minutes. Leave to cool well in the refrigerator. Dust with icing sugar as desired and decorate with lime slices. Results in approx. 12 pieces