Mix flour with sugar. Add butter in pieces and water. Chop through everything with a knife to form dry crumbs. Then knead everything quickly by hand to a smooth dough.
Wrap the dough in foil and place in the refrigerator for about 30 minutes.
Roll out the dough on a floured surface and line a greased tart mould (approx. 26-28 cm diameter, or 2 small moulds approx. 18-20 cm diameter) with the dough. Prick the dough several times with a fork.
Place the mould in the refrigerator for about 1 hour. Then place a sheet of baking paper on top and pour the peas on top.
Pre-bake in the preheated oven at 200 degrees (gas: level 3-4, fan oven: 180 degrees) for approx. 15 minutes. Remove peas and baking paper. Switch the temperature down to 160 degrees (gas: level 1-2, fan oven: 140 degrees).
Rinse limes, grate peel and squeeze juice. Whip cream until stiff. Mix mascarpone with lime juice and zest, sugar, vanilla sugar and eggs well. Fold in cream. Spread 3/4 of the cranberries on the tart base, then pour the mascarpone mixture on top.
Bake the tart in the oven for about 30 minutes. Let it cool down.
Sprinkle the remaining cranberries over the tart and garnish with slices of lime. Serve dusted with icing sugar.